diff --git a/tools/chatgui-android/app/src/main/java/com/utun/chat/data/NativeLib.kt b/tools/chatgui-android/app/src/main/java/com/utun/chat/data/NativeLib.kt
index cb18de52..bf208bf6 100644
--- a/tools/chatgui-android/app/src/main/java/com/utun/chat/data/NativeLib.kt
+++ b/tools/chatgui-android/app/src/main/java/com/utun/chat/data/NativeLib.kt
@@ -207,7 +207,18 @@ object NativeLib {
                    width: Int = 0, height: Int = 0, rotation: Int = 0, audio: Boolean = true): Int =
         nativeStreamFeed(id, video, pts, key, data, revision, width, height, rotation, audio)
     fun streamStop(id: Long) { nativeStreamStop(id) }
-    fun streamPull(id: Long): ByteArray? = nativeStreamPull(id)
+    fun streamPull(id: Long, positionUs: Long = -1, videoAheadUs: Long = 80000, audioAheadUs: Long = 80000): ByteArray? =
+        nativeStreamPull(id, positionUs, videoAheadUs, audioAheadUs)
+    fun streamStatus(id: Long): LongArray? = nativeStreamStatus(id)
+    fun streamResync(id: Long): Boolean = nativeStreamResync(id)
+    fun streamPlaybackCreate(id: Long, pts: Long, audio: Boolean): Long = nativeStreamPlaybackCreate(id, pts, audio)
+    fun streamPlaybackFeed(handle: Long, pts: Long, packet: ByteArray): Int = nativeStreamPlaybackFeed(handle, pts, packet)
+    fun streamPlaybackPull(handle: Long, frames: Int, limit: Long): ShortArray? = nativeStreamPlaybackPull(handle, frames, limit)
+    fun streamPlaybackUpdate(handle: Long, now: Long, played: Long, ready: Long, guard: Long, starved: Boolean): LongArray? =
+        nativeStreamPlaybackUpdate(handle, now, played, ready, guard, starved)
+    fun streamPlaybackFinish(handle: Long) { nativeStreamPlaybackFinish(handle) }
+    fun streamPlaybackEmpty(handle: Long): Boolean = nativeStreamPlaybackEmpty(handle)
+    fun streamPlaybackClose(handle: Long) { nativeStreamPlaybackClose(handle) }
     fun streamOpusCreate(encode: Boolean): Long = nativeStreamOpusCreate(encode)
     fun streamOpusEncode(handle: Long, pcm: ShortArray, compressor: RadioCompressorSettings): ByteArray? =
         nativeStreamOpusEncode(handle, pcm, compressor.enabled, compressor.maxGainDb, compressor.riseRate)
@@ -219,7 +230,17 @@ object NativeLib {
     private external fun nativeStreamFeed(id: Long, video: Boolean, pts: Long, key: Boolean, data: ByteArray,
                                          revision: Long, width: Int, height: Int, rotation: Int, audio: Boolean): Int
     private external fun nativeStreamStop(id: Long)
-    private external fun nativeStreamPull(id: Long): ByteArray?
+    private external fun nativeStreamPull(id: Long, position: Long, videoAhead: Long, audioAhead: Long): ByteArray?
+    private external fun nativeStreamStatus(id: Long): LongArray?
+    private external fun nativeStreamResync(id: Long): Boolean
+    private external fun nativeStreamPlaybackCreate(id: Long, pts: Long, audio: Boolean): Long
+    private external fun nativeStreamPlaybackFeed(handle: Long, pts: Long, packet: ByteArray): Int
+    private external fun nativeStreamPlaybackPull(handle: Long, frames: Int, limit: Long): ShortArray?
+    private external fun nativeStreamPlaybackUpdate(handle: Long, now: Long, played: Long, ready: Long,
+                                                   guard: Long, starved: Boolean): LongArray?
+    private external fun nativeStreamPlaybackFinish(handle: Long)
+    private external fun nativeStreamPlaybackEmpty(handle: Long): Boolean
+    private external fun nativeStreamPlaybackClose(handle: Long)
     private external fun nativeStreamOpusCreate(encode: Boolean): Long
     private external fun nativeStreamOpusEncode(handle: Long, pcm: ShortArray, compressor: Boolean, maxGainDb: Int, riseRate: Int): ByteArray?
     private external fun nativeStreamOpusDecode(handle: Long, packet: ByteArray): ShortArray?
diff --git a/tools/chatgui-android/app/src/main/java/com/utun/chat/data/StreamPlayerEngine.kt b/tools/chatgui-android/app/src/main/java/com/utun/chat/data/StreamPlayerEngine.kt
index 4e6bc19b..c8b7f429 100644
--- a/tools/chatgui-android/app/src/main/java/com/utun/chat/data/StreamPlayerEngine.kt
+++ b/tools/chatgui-android/app/src/main/java/com/utun/chat/data/StreamPlayerEngine.kt
@@ -15,15 +15,15 @@ import java.nio.ByteOrder
 import java.util.ArrayDeque
 import java.util.concurrent.locks.ReentrantLock
 import kotlin.concurrent.withLock
-import kotlin.math.roundToInt
 
-/** Один worker владеет декодерами и AudioTrack. Hardware audio clock управляет временем показа видео.
- * Просроченные P-кадры декодируются без показа, чтобы сохранить references; при переполнении ждём KEY.
- * viewerLock сериализует stop/open разных экранов до подтверждения освобождения native owner. */
+/** Запас кодированного потока остаётся в общем RS-кольце. Worker запрашивает ближайшие кадры,
+ * общий native controller ведёт минутную историю и темп, AudioTrack задаёт фактические часы.
+ * Временная нехватка сохраняет decoder references; GAP/вытеснение начинают новую точку KEY. */
 class StreamPlayerEngine(private val group: Long, private val source: Long, private val epoch: Long,
                          private val localPreview: StreamPreview? = null, private val displayDegrees: Int = 0) {
     companion object { private val viewerLock = ReentrantLock() }
-    private data class Frame(val pts: Long, val key: Boolean, val width: Int, val height: Int, val rotation: Int, val top: Int?, val revision: Long, val data: ByteArray)
+    private data class Frame(val pts: Long, val key: Boolean, val width: Int, val height: Int,
+                             val rotation: Int, val top: Int?, val revision: Long, val data: ByteArray)
     private val mutableAspect = MutableStateFlow(16f / 9f)
     val aspect: StateFlow<Float> = mutableAspect
     private val mutableTop = MutableStateFlow<Int?>(null)
@@ -39,294 +39,238 @@ class StreamPlayerEngine(private val group: Long, private val source: Long, priv
         running = true
         worker = Thread({ viewerLock.withLock { if (running) play(surface) } }, "stream-player").apply { start() }
     }
-
     fun stop() { running = false; NativeLib.streamStop(id) }
 
     private fun play(surface: Surface) {
         var decoder: MediaCodec? = null
         var track: AudioTrack? = null
-        var opus = 0L
-        val videos = ArrayDeque<Frame>(); val audios = ArrayDeque<Frame>()
-        var videoBytes = 0
+        var playback = 0L
+        val videos = ArrayDeque<Frame>()
+        val submitted = ArrayDeque<Long>()
         var waitingKey = true
-        var audioBase = -1L
-        var written = 0L
-        var videoBase = -1L
-        var videoStartNs = 0L
+        var audioEnabled = false
+        var opened = false
         var ended = false
-        val audioTimestamp = AudioTimestamp()
-        val bufferInfo = MediaCodec.BufferInfo()
-        var report = 0L
+        var pausedAudio = false
         var videoRevision = 0L
-        var reportedDecoded = 0L
+        var position = -1L
+        var ready = -1L
+        var needsAudio = true
+        var written = 0L
+        var previousHead = 0L
+        var headEpoch = 0L
+        var generation = 0L
         var decoded = 0L
         var discarded = 0L
-        var lastHead = -1L
-        var headChangedNs = 0L
-        var endDrainUntil = 0L
-        var headEpoch = 0L
-        var previousRawHead = 0L
-        var prefillUntil = 0L
-        var firstAudioSkipFrames = 0
-        var prerollFrames = 0L
-        var warmAudioPts = -1L
-        var connectDeadline = System.nanoTime() + 10_000_000_000
+        var decodedThrough = -1L
+        var pendingOutput = -1
+        var pendingPts = 0L
+        var eosQueued = false
+        var decoderEnded = false
+        var endUntil = 0L
+        var reported = 0L
+        var deadline = System.nanoTime() + 10_000_000_000
+        val timestamp = AudioTimestamp()
+        val info = MediaCodec.BufferInfo()
+        var clockState: LongArray? = null
 
         fun resetVideo() {
-            try { decoder?.stop() }
+            try { decoder?.stop(); decoder?.release() }
             catch (e: Exception) { LogManager.addLog("WARN", "video", "decoder reset id=$id: ${e.message}") }
-            try { decoder?.release() }
-            catch (e: Exception) { LogManager.addLog("WARN", "video", "decoder release id=$id: ${e.message}") }
-            decoder = null; videos.clear(); videoBytes = 0; waitingKey = true
+            decoder = null; videos.clear(); submitted.clear(); pendingOutput = -1; decodedThrough = -1
+            waitingKey = true; eosQueued = false; decoderEnded = false
             mutableStatus.value = R.string.stream_waiting_key
         }
-        fun resetAudio() {
-            try { track?.pause(); track?.flush() }
+        fun resetTimeline(request: Boolean) {
+            try { track?.pause(); track?.flush(); track?.release() }
             catch (e: Exception) { LogManager.addLog("WARN", "stream", "audio reset id=$id: ${e.message}") }
-            try { track?.release() }
-            catch (e: Exception) { LogManager.addLog("WARN", "stream", "audio release id=$id: ${e.message}") }
-            track = null
-            if (opus != 0L) NativeLib.streamOpusClose(opus)
-            opus = 0; audioBase = -1; written = 0; lastHead = -1; headEpoch = 0; previousRawHead = 0; audios.clear()
-            firstAudioSkipFrames = 0; prerollFrames = 0; warmAudioPts = -1
-        }
-        fun resetTimeline() {
-            resetAudio(); resetVideo(); videoBase = -1; prefillUntil = 0
-            connectDeadline = System.nanoTime() + 10_000_000_000
-        }
-        // Прогрев допускает джиттер PTS и короткий PLC; большой разрыв начинает новое состояние Opus.
-        fun prepareAudio(pts: Long) {
-            if (warmAudioPts >= 0 && (pts < warmAudioPts - 10000 || pts > warmAudioPts + 100000)) {
-                LogManager.addLog("WARN", "stream", "preroll audio discontinuity id=$id expected=$warmAudioPts pts=$pts")
-                if (opus != 0L) NativeLib.streamOpusClose(opus)
-                opus = 0; warmAudioPts = -1
-            }
-            if (opus == 0L) { opus = NativeLib.streamOpusCreate(false); check(opus != 0L) }
-            val missing = if (warmAudioPts < 0) 0 else ((pts - warmAudioPts + 10000) / 20000).toInt()
-            repeat(missing) {
-                check(NativeLib.streamOpusDecode(opus, byteArrayOf()) != null) { "Preroll Opus PLC failed" }
-                prerollFrames += 960
-            }
+            track = null; pausedAudio = false; written = 0; previousHead = 0; headEpoch = 0
+            if (playback != 0L) NativeLib.streamPlaybackClose(playback)
+            playback = 0; position = -1; generation = 0; needsAudio = true; clockState = null
+            resetVideo(); deadline = System.nanoTime() + 10_000_000_000
+            if (request) check(NativeLib.streamResync(id)) { "Media resync refused" }
         }
-        // Отброшенный звук всё равно прогревает Opus; остающиеся пакеты декодируются один раз при воспроизведении.
-        fun warmAudio(frame: Frame) {
-            prepareAudio(frame.pts)
-            check(NativeLib.streamOpusDecode(opus, frame.data) != null) { "Preroll Opus decode failed" }
-            warmAudioPts = frame.pts + 20000; prerollFrames += 960
-        }
-        // PlaybackHeadPosition — unsigned 32 bit: при 48kHz оборачивается примерно через 25 часов.
-        fun playedFrames(t: AudioTrack): Long {
+        fun playedFrames(now: Long): Long {
+            val t = track ?: return 0
             val raw = t.playbackHeadPosition.toLong() and 0xffffffffL
-            if (raw < previousRawHead) headEpoch += 0x100000000L
-            previousRawHead = raw
-            return headEpoch + raw
-        }
-        fun currentPts(now: Long): Long {
-            val t = track
-            if (t != null && audioBase >= 0) {
-                val head = playedFrames(t)
-                val played = if (t.getTimestamp(audioTimestamp)) {
-                    var position = audioTimestamp.framePosition
-                    if (position <= 0xffffffffL) {
-                        position += headEpoch
-                        if (position - head > 0x80000000L) position -= 0x100000000L
-                        if (head - position > 0x80000000L) position += 0x100000000L
-                    }
-                    position + (now - audioTimestamp.nanoTime).coerceAtLeast(0) * 48000 / 1_000_000_000
-                } else {
-                    if (head != lastHead) { lastHead = head; headChangedNs = now }
-                    head + if (head >= written) (now - headChangedNs) * 48000 / 1_000_000_000 else 0
-                }
-                return audioBase + played * 1_000_000 / 48000
+            if (raw < previousHead) headEpoch += 0x100000000L
+            previousHead = raw
+            val head = headEpoch + raw
+            if (pausedAudio || !t.getTimestamp(timestamp)) return head.coerceAtMost(written)
+            var frames = timestamp.framePosition
+            if (frames <= 0xffffffffL) {
+                frames += headEpoch
+                if (frames - head > 0x80000000L) frames -= 0x100000000L
+                if (head - frames > 0x80000000L) frames += 0x100000000L
             }
-            return if (videoBase >= 0) videoBase + (now - videoStartNs) / 1000 else 0
+            return (frames + (now - timestamp.nanoTime).coerceAtLeast(0) * 48000 / 1_000_000_000).coerceIn(0, written)
         }
-        fun writePcm(t: AudioTrack, pcm: ShortArray, initialOffset: Int = 0) {
-            val deadline = System.nanoTime() + 100_000_000
-            var offset = initialOffset
+        fun writePcm(pcm: ShortArray) {
+            if (track == null) {
+                track = AudioTrack.Builder().setAudioAttributes(AudioAttributes.Builder().setUsage(AudioAttributes.USAGE_MEDIA)
+                    .setContentType(AudioAttributes.CONTENT_TYPE_MOVIE).build()).setAudioFormat(AudioFormat.Builder()
+                    .setSampleRate(48000).setChannelMask(AudioFormat.CHANNEL_OUT_STEREO).setEncoding(AudioFormat.ENCODING_PCM_16BIT).build())
+                    .setBufferSizeInBytes(AudioTrack.getMinBufferSize(48000, AudioFormat.CHANNEL_OUT_STEREO,
+                        AudioFormat.ENCODING_PCM_16BIT).coerceAtLeast(3840)).setTransferMode(AudioTrack.MODE_STREAM).build()
+                check(track!!.state == AudioTrack.STATE_INITIALIZED); track!!.play()
+                LogManager.addLog("INFO", "stream", "audio output id=$id bufferFrames=${track!!.bufferSizeInFrames} stereo=1")
+            }
+            val until = System.nanoTime() + 100_000_000
+            var offset = 0
             while (running && offset < pcm.size) {
-                val count = t.write(pcm, offset, pcm.size - offset, AudioTrack.WRITE_NON_BLOCKING)
-                check(count >= 0) { "AudioTrack write=$count" }
-                if (count > 0) {
-                    check(count % 2 == 0) { "AudioTrack returned an incomplete stereo frame: samples=$count" }
-                    offset += count; written += count / 2
-                }
-                else {
-                    check(System.nanoTime() < deadline) { "AudioTrack stalled for 100ms" }
-                    Thread.sleep(2)
-                }
+                val count = track!!.write(pcm, offset, pcm.size - offset, AudioTrack.WRITE_NON_BLOCKING)
+                check(count >= 0 && count % 2 == 0) { "AudioTrack write=$count" }
+                if (count > 0) { offset += count; written += count / 2 }
+                else { check(System.nanoTime() < until) { "AudioTrack stalled" }; Thread.sleep(2) }
             }
         }
         try {
-            check(NativeLib.streamOpen(id, group, source, epoch = epoch)) { "Viewer open refused" }
-            var opened = false
+            check(NativeLib.streamOpen(id, group, source, audio = localPreview == null, epoch = epoch)) { "Viewer open refused" }
             while (running && surface.isValid) {
-                if (!NativeLib.isReady()) error("Core stopped")
-                repeat(64) {
-                    val raw = if (!ended) NativeLib.streamPull(id) else null
-                    if (raw != null) {
-                        check(raw.size >= 24)
-                        val b = ByteBuffer.wrap(raw).order(ByteOrder.BIG_ENDIAN)
-                        val kind = b.get().toInt(); val flags = b.get().toInt() and 255; val key = flags and 1 != 0
-                        val width = b.short.toInt() and 65535; val height = b.short.toInt() and 65535
-                        val broadcastRotation = b.short.toInt() and 65535; val pts = b.long; val size = b.int
-                        val revision = b.int.toLong() and 0xffffffffL
-                        check(size == b.remaining())
-                        when (kind) {
-                            1, 2 -> {
-                                val camera = if (kind == 1) localPreview?.camera(revision) else null
-                                if (kind == 1 && localPreview != null && camera == null) {
-                                    LogManager.addLog("WARN", "video", "preview camera unavailable id=$id revision=$revision; wait KEY")
-                                    resetVideo(); return@repeat
-                                }
-                                val display = StreamVideoDisplay.forFrame(broadcastRotation, camera, displayDegrees)
-                                val rotation = display.rotation
-                                val frame = Frame(pts, key, width, height, rotation, display.top, revision, ByteArray(size).also { b.get(it) })
-                                if (kind == 1) {
-                                    if (revision != videoRevision) {
-                                        check(revision > videoRevision) { "Video revision regressed" }
-                                        LogManager.addLog("INFO", "video", "viewer configuration id=$id revision=$videoRevision->$revision ${width}x$height " +
-                                            "rotation=$rotation broadcastRotation=$broadcastRotation preview=${localPreview != null} top=${display.top}")
-                                        resetVideo(); videoRevision = revision
-                                    }
-                                    if (videos.size >= 128 || videoBytes + size > H264AnnexB.MAX_FRAME ||
-                                        (videos.isNotEmpty() && pts - videos.first.pts > 250000)) {
-                                        LogManager.addLog("WARN", "video", "viewer video overflow id=$id frames=${videos.size} bytes=$videoBytes revision=$revision")
-                                        resetVideo()
-                                    }
-                                    if (!waitingKey || key) {
-                                        if (waitingKey) {
-                                            check(H264AnnexB.nals(frame.data).map { it.first }.toSet().containsAll(setOf(5, 7, 8)))
-                                            waitingKey = false
-                                            mutableAspect.value = if (rotation % 180 == 0) width.toFloat() / height else height.toFloat() / width
-                                            mutableTop.value = frame.top
-                                        }
-                                        if (videoBase < 0) {
-                                            while (audios.isNotEmpty() && audios.first.pts + 20000 <= pts) warmAudio(audios.removeFirst())
-                                            if (audios.isNotEmpty() && audios.first.pts < pts)
-                                                firstAudioSkipFrames = ((pts - audios.first.pts) * 48000 + 999999).div(1000000).toInt()
-                                            prefillUntil = System.nanoTime() + 150_000_000
-                                            videoBase = pts; videoStartNs = prefillUntil
-                                            LogManager.addLog("INFO", "stream", "viewer playback start id=$id pts=$pts prefillMs=150 " +
-                                                "prerollFrames=$prerollFrames skipFrames=$firstAudioSkipFrames audioQ=${audios.size}")
-                                        }
-                                        videos.addLast(frame); videoBytes += size
-                                    }
-                                } else {
-                                    if (localPreview != null) return@repeat
-                                    if (audios.size >= 16) {
-                                        if (videoBase < 0) warmAudio(audios.removeFirst())
-                                        else {
-                                            LogManager.addLog("WARN", "stream", "audio queue overflow id=$id; reset timeline")
-                                            resetTimeline()
-                                        }
-                                    }
-                                    audios.addLast(frame)
-                                }
+                check(NativeLib.isReady()) { "Core stopped" }
+                val meta = NativeLib.streamStatus(id)
+                if (meta != null && meta[5] and 1 != 0L) {
+                    ready = if (localPreview != null) meta[1] else meta[0]
+                    if (playback == 0L) {
+                        audioEnabled = localPreview == null && meta[5] and 2 != 0L
+                        playback = NativeLib.streamPlaybackCreate(id, meta[3], audioEnabled)
+                        check(playback != 0L); position = meta[3]; generation = meta[4]
+                        LogManager.addLog("INFO", "stream", "playback starts id=$id PTS=$position generation=$generation fixedPrefill=0")
+                    }
+                }
+                val now = System.nanoTime()
+                val played = playedFrames(now)
+                val deviceLead = (written - played).coerceAtLeast(0) * 1_000_000 / 48000
+                val videoAhead = if (videos.size < 2 && submitted.size < 3) 80000L else -1L
+                val audioAhead = if (audioEnabled && needsAudio) deviceLead + 80000 else -1L
+                repeat(4) {
+                    val raw = if (ended) null else NativeLib.streamPull(id, position, videoAhead, audioAhead)
+                    if (raw == null) return@repeat
+                    check(raw.size >= 24)
+                    val b = ByteBuffer.wrap(raw).order(ByteOrder.BIG_ENDIAN)
+                    val kind = b.get().toInt(); val flags = b.get().toInt() and 255
+                    val width = b.short.toInt() and 65535; val height = b.short.toInt() and 65535
+                    val broadcastRotation = b.short.toInt() and 65535; val pts = b.long; val size = b.int
+                    val revision = b.int.toLong() and 0xffffffffL
+                    check(size == b.remaining())
+                    when (kind) {
+                        1 -> {
+                            val camera = localPreview?.camera(revision)
+                            if (localPreview != null && camera == null) {
+                                LogManager.addLog("WARN", "video", "preview camera unavailable id=$id revision=$revision")
+                                resetTimeline(true); return@repeat
+                            }
+                            val display = StreamVideoDisplay.forFrame(broadcastRotation, camera, displayDegrees)
+                            if (revision != videoRevision) {
+                                check(revision > videoRevision); resetVideo(); videoRevision = revision
+                                deadline = System.nanoTime() + 10_000_000_000
                             }
-                            3 -> { LogManager.addLog("INFO", "stream", "viewer GAP id=$id"); resetTimeline() }
-                            4 -> opened = true
-                            5 -> { ended = true; if (videoBase < 0) audios.clear() }
-                            6 -> {
-                                mutableStatus.value = when (flags) {
-                                    1 -> R.string.stream_group_closed
-                                    2 -> R.string.chat_service_stopped
-                                    3 -> R.string.stream_source_changed
-                                    4 -> R.string.stream_member_removed
-                                    else -> R.string.stream_failed
+                            val key = flags and 1 != 0
+                            if (!waitingKey || key) {
+                                val bytes = ByteArray(size).also { b.get(it) }
+                                if (waitingKey) {
+                                    check(H264AnnexB.nals(bytes).map { it.first }.toSet().containsAll(setOf(5, 7, 8)))
+                                    waitingKey = false; mutableTop.value = display.top
+                                    mutableAspect.value = if (display.rotation % 180 == 0) width.toFloat() / height else height.toFloat() / width
                                 }
-                                LogManager.addLog("WARN", "stream", "native viewer closed id=$id group=$group source=$source epoch=$epoch reason=$flags")
-                                ended = true; running = false
+                                check(videos.size < 4) { "Video preparation queue exceeded" }
+                                videos.addLast(Frame(pts, key, width, height, display.rotation, display.top, revision, bytes))
+                            }
+                        }
+                        2 -> if (audioEnabled && playback != 0L) {
+                            val result = NativeLib.streamPlaybackFeed(playback, pts, ByteArray(size).also { b.get(it) })
+                            if (result == -2) resetTimeline(true) else check(result >= 0) { "Opus feed failed=$result" }
+                        }
+                        3 -> { LogManager.addLog("INFO", "stream", "playback GAP id=$id"); resetTimeline(false) }
+                        4 -> opened = true
+                        5 -> { ended = true; if (playback != 0L) NativeLib.streamPlaybackFinish(playback) }
+                        6 -> {
+                            mutableStatus.value = when (flags) {
+                                1 -> R.string.stream_group_closed; 2 -> R.string.chat_service_stopped
+                                3 -> R.string.stream_source_changed; 4 -> R.string.stream_member_removed
+                                else -> R.string.stream_failed
                             }
-                            else -> error("Unknown media event=$kind")
+                            LogManager.addLog("WARN", "stream", "native viewer closed id=$id reason=$flags"); running = false
                         }
+                        else -> error("Unknown media event=$kind")
                     }
                 }
-                if (!ended && (!opened || videoBase < 0) && System.nanoTime() > connectDeadline) error("Viewer open timeout")
-                val now = System.nanoTime()
-                if (prefillUntil != 0L && now >= prefillUntil) {
-                    if (audios.isNotEmpty() && track == null) {
-                        prepareAudio(audios.first.pts)
-                        track = AudioTrack.Builder().setAudioAttributes(AudioAttributes.Builder().setUsage(AudioAttributes.USAGE_MEDIA)
-                            .setContentType(AudioAttributes.CONTENT_TYPE_MOVIE).build()).setAudioFormat(AudioFormat.Builder()
-                            .setSampleRate(48000).setChannelMask(AudioFormat.CHANNEL_OUT_STEREO).setEncoding(AudioFormat.ENCODING_PCM_16BIT).build())
-                            .setBufferSizeInBytes(AudioTrack.getMinBufferSize(48000, AudioFormat.CHANNEL_OUT_STEREO, AudioFormat.ENCODING_PCM_16BIT)
-                                .coerceAtLeast(19200)).setTransferMode(AudioTrack.MODE_STREAM).build()
-                        check(track!!.state == AudioTrack.STATE_INITIALIZED)
-                        audioBase = audios.first.pts + firstAudioSkipFrames * 1_000_000L / 48000
-                        track!!.play()
-                        LogManager.addLog("INFO", "stream", "audio playback starts id=$id PTS=$audioBase rate=48000 channels=${track!!.channelCount}")
-                    }
+                if (!ended && (!opened || waitingKey) && System.nanoTime() > deadline) error("Viewer open timeout")
+                if (playback != 0L && audioEnabled && !pausedAudio) {
+                    val head = playedFrames(System.nanoTime())
                     val t = track
-                    if (t != null && audios.isNotEmpty()) {
-                        val head = playedFrames(t)
-                        if (written - head < 3840) {
-                            val f = audios.removeFirst()
-                            val pts = f.pts + firstAudioSkipFrames * 1_000_000L / 48000
-                            val missing = ((pts - audioBase - written * 1_000_000 / 48000).toDouble() / 20000).roundToInt()
-                            if (missing > 5 || missing < -5) {
-                                LogManager.addLog("WARN", "stream", "audio discontinuity id=$id missing=$missing packets")
-                                resetTimeline(); audios.addFirst(f)
-                            } else if (missing >= 0) {
-                                repeat(missing) {
-                                    val conceal = NativeLib.streamOpusDecode(opus, byteArrayOf()) ?: error("Opus PLC failed")
-                                    writePcm(t, conceal)
-                                }
-                                val pcm = NativeLib.streamOpusDecode(opus, f.data) ?: error("Opus decode failed")
-                                writePcm(t, pcm, firstAudioSkipFrames * 2); firstAudioSkipFrames = 0
-                            } else LogManager.addLog("DEBUG", "stream", "late audio discarded id=$id pts=${f.pts}")
+                    val prime = t == null || (head == 0L && written < t.bufferSizeInFrames)
+                    if (prime || written - head < 960) {
+                        NativeLib.streamPlaybackPull(playback, 480, if (ended) Long.MAX_VALUE else ready)?.let { writePcm(it) }
+                    }
+                }
+                if (playback != 0L && ready >= 0) {
+                    val lateVideo = submitted.isNotEmpty() && submitted.first < position - 10000
+                    if (lateVideo && track != null && !pausedAudio) { track!!.pause(); pausedAudio = true }
+                    if (pausedAudio && !lateVideo) { track!!.play(); pausedAudio = false }
+                    val head = playedFrames(System.nanoTime())
+                    val audioEmpty = audioEnabled && written > 0 && head >= written && !ended
+                    clockState = NativeLib.streamPlaybackUpdate(playback, System.nanoTime() / 1000, head,
+                        if (ended) ready.coerceAtLeast(position) else ready,
+                        (deviceLead + 10000).coerceAtLeast(33333), lateVideo || audioEmpty)
+                    check(clockState != null) { "Playback timeline failed" }
+                    position = clockState!![0]; needsAudio = clockState!![5] != 0L
+                }
+                repeat(4) {
+                    if (videos.isEmpty()) return@repeat
+                    val frame = videos.first
+                    if (decoder == null) {
+                        check(frame.key)
+                        val nals = H264AnnexB.nals(frame.data)
+                        val format = MediaFormat.createVideoFormat(MediaFormat.MIMETYPE_VIDEO_AVC, frame.width, frame.height).apply {
+                            setByteBuffer("csd-0", ByteBuffer.wrap(nals.first { it.first == 7 }.second))
+                            setByteBuffer("csd-1", ByteBuffer.wrap(nals.first { it.first == 8 }.second))
+                            setInteger(MediaFormat.KEY_ROTATION, frame.rotation); setInteger(MediaFormat.KEY_MAX_INPUT_SIZE, H264AnnexB.MAX_FRAME)
                         }
+                        decoder = MediaCodec.createDecoderByType(MediaFormat.MIMETYPE_VIDEO_AVC)
+                        decoder!!.configure(format, surface, null, 0); decoder!!.start()
+                    }
+                    val index = decoder!!.dequeueInputBuffer(0)
+                    if (index >= 0) {
+                        val input = decoder!!.getInputBuffer(index) ?: error("Missing decoder input")
+                        check(frame.data.size <= input.capacity()); input.clear(); input.put(frame.data)
+                        decoder!!.queueInputBuffer(index, 0, frame.data.size, frame.pts, 0)
+                        submitted.addLast(frame.pts); videos.removeFirst(); decoded++
+                    }
+                }
+                val codec = decoder
+                if (codec != null) {
+                    if (ended && videos.isEmpty() && !eosQueued) {
+                        val index = codec.dequeueInputBuffer(0)
+                        if (index >= 0) { codec.queueInputBuffer(index, 0, 0, decodedThrough.coerceAtLeast(0) + 1,
+                            MediaCodec.BUFFER_FLAG_END_OF_STREAM); eosQueued = true }
                     }
-                    val clock = currentPts(now)
                     repeat(8) {
-                        if (videos.isEmpty() || videos.first.pts > clock + 80000) return@repeat
-                        val frame = videos.first
-                        if (decoder == null) {
-                            check(frame.key)
-                            val nals = H264AnnexB.nals(frame.data)
-                            val format = MediaFormat.createVideoFormat(MediaFormat.MIMETYPE_VIDEO_AVC, frame.width, frame.height).apply {
-                                setByteBuffer("csd-0", ByteBuffer.wrap(nals.first { it.first == 7 }.second))
-                                setByteBuffer("csd-1", ByteBuffer.wrap(nals.first { it.first == 8 }.second))
-                                setInteger(MediaFormat.KEY_ROTATION, frame.rotation); setInteger(MediaFormat.KEY_MAX_INPUT_SIZE, H264AnnexB.MAX_FRAME)
+                        if (pendingOutput < 0) {
+                            val index = codec.dequeueOutputBuffer(info, 0)
+                            if (index < 0) return@repeat
+                            if (info.flags and MediaCodec.BUFFER_FLAG_END_OF_STREAM != 0 && info.size == 0) {
+                                codec.releaseOutputBuffer(index, false); decoderEnded = true; return@repeat
                             }
-                            decoder = MediaCodec.createDecoderByType(MediaFormat.MIMETYPE_VIDEO_AVC)
-                            decoder!!.configure(format, surface, null, 0); decoder!!.start()
-                            LogManager.addLog("INFO", "video", "decoder started id=$id ${frame.width}x${frame.height} rotation=${frame.rotation}")
-                        }
-                        val index = decoder!!.dequeueInputBuffer(0)
-                        if (index >= 0) {
-                            val input = decoder!!.getInputBuffer(index) ?: error("Missing decoder input")
-                            check(frame.data.size <= input.capacity()) { "Decoder input too small" }
-                            input.clear(); input.put(frame.data)
-                            decoder!!.queueInputBuffer(index, 0, frame.data.size, frame.pts, 0)
-                            videos.removeFirst(); videoBytes -= frame.data.size; decoded++
-                        } else if (clock - frame.pts > 250000) {
-                            LogManager.addLog("WARN", "video", "decoder backpressure id=$id ageUs=${clock - frame.pts}; wait KEY")
-                            resetVideo()
-                        }
-                    }
-                    val codec = decoder
-                    if (codec != null) repeat(16) {
-                        val index = codec.dequeueOutputBuffer(bufferInfo, 0)
-                        if (index >= 0) {
-                            val clockPts = currentPts(System.nanoTime())
-                            if (bufferInfo.presentationTimeUs < clockPts - 100000) {
-                                codec.releaseOutputBuffer(index, false); discarded++
-                            } else codec.releaseOutputBuffer(index, System.nanoTime() + (bufferInfo.presentationTimeUs - clockPts).coerceAtLeast(0) * 1000)
-                            mutableStatus.value = R.string.stream_live
+                            pendingOutput = index; pendingPts = info.presentationTimeUs; decodedThrough = pendingPts
+                            while (submitted.isNotEmpty() && submitted.first <= pendingPts) submitted.removeFirst()
                         }
+                        if (pendingPts > position) return@repeat
+                        val render = pendingPts >= position - 100000
+                        codec.releaseOutputBuffer(pendingOutput, render); pendingOutput = -1
+                        if (!render) discarded++ else mutableStatus.value = R.string.stream_live
                     }
                 }
-                if (ended && videos.isEmpty() && audios.isEmpty()) {
-                    if (endDrainUntil == 0L) endDrainUntil = now + 250_000_000
-                    if (now >= endDrainUntil) { mutableStatus.value = R.string.stream_ended; break }
+                if (ended && videos.isEmpty() && (decoder == null || decoderEnded) && NativeLib.streamPlaybackEmpty(playback)
+                    && playedFrames(System.nanoTime()) >= written) {
+                    if (endUntil == 0L) endUntil = System.nanoTime() + 100_000_000
+                    if (System.nanoTime() >= endUntil) { mutableStatus.value = R.string.stream_ended; break }
                 }
-                if (now - report >= 1_000_000_000) {
-                    val seconds = if (report == 0L) 1.0 else (now - report) / 1_000_000_000.0
-                    report = now
-                    LogManager.addLog("DEBUG", "stream", "viewer id=$id revision=$videoRevision decodeFps=${"%.1f".format((decoded - reportedDecoded) / seconds)} decoded=$decoded discarded=$discarded videoQ=${videos.size}/$videoBytes " +
-                        "audioQ=${audios.size} written=$written clock=${currentPts(now)} waitingKey=$waitingKey")
-                    reportedDecoded = decoded
+                if (System.nanoTime() - reported >= 1_000_000_000) {
+                    reported = System.nanoTime()
+                    LogManager.addLog("DEBUG", "stream", "viewer id=$id revision=$videoRevision decoded=$decoded discarded=$discarded " +
+                        "videoQ=${videos.size} submitted=${submitted.size} clock=$position reserve=${clockState?.get(1)} " +
+                        "minimum=${clockState?.get(2)} tempo=${clockState?.get(3)} written=$written waitingKey=$waitingKey")
                 }
                 Thread.sleep(5)
             }
@@ -334,13 +278,13 @@ class StreamPlayerEngine(private val group: Long, private val source: Long, priv
             if (running) { mutableStatus.value = R.string.stream_failed; LogManager.addLog("ERROR", "stream", "viewer failed id=$id: ${e.message}") }
         } finally {
             NativeLib.streamStop(id)
-            try { decoder?.stop() } catch (e: Exception) { LogManager.addLog("WARN", "video", "decoder stop id=$id: ${e.message}") }
-            try { decoder?.release() } catch (e: Exception) { LogManager.addLog("WARN", "video", "decoder release id=$id: ${e.message}") }
-            try { track?.stop() } catch (e: Exception) { LogManager.addLog("WARN", "stream", "audio stop id=$id: ${e.message}") }
-            try { track?.release() } catch (e: Exception) { LogManager.addLog("WARN", "stream", "audio release id=$id: ${e.message}") }
-            if (opus != 0L) NativeLib.streamOpusClose(opus)
-            val deadline = System.nanoTime() + 500_000_000
-            while (!ended && NativeLib.isReady() && System.nanoTime() < deadline) {
+            try { decoder?.stop(); decoder?.release() }
+            catch (e: Exception) { LogManager.addLog("WARN", "video", "decoder release id=$id: ${e.message}") }
+            try { track?.stop(); track?.release() }
+            catch (e: Exception) { LogManager.addLog("WARN", "stream", "audio release id=$id: ${e.message}") }
+            if (playback != 0L) NativeLib.streamPlaybackClose(playback)
+            val until = System.nanoTime() + 500_000_000
+            while (NativeLib.isReady() && System.nanoTime() < until) {
                 val event = NativeLib.streamPull(id)
                 if (event != null && event[0].toInt() in 5..6) break
                 Thread.sleep(5)