diff --git a/tools/chatgui-android/app/src/main/java/com/utun/chat/data/StreamCaptureEngine.kt b/tools/chatgui-android/app/src/main/java/com/utun/chat/data/StreamCaptureEngine.kt
index 5f53e36c..adf05e2a 100644
--- a/tools/chatgui-android/app/src/main/java/com/utun/chat/data/StreamCaptureEngine.kt
+++ b/tools/chatgui-android/app/src/main/java/com/utun/chat/data/StreamCaptureEngine.kt
@@ -166,8 +166,7 @@ class StreamCaptureEngine(
                                 buffer.position(info.offset); buffer.limit(info.offset + info.size)
                                 val bytes = ByteArray(info.size).also { buffer.get(it) }
                                 if (info.flags and MediaCodec.BUFFER_FLAG_CODEC_CONFIG != 0) {
-                                    val codecConfig = mode.videoCodec.normalize(bytes)
-                                    check(codecConfig.size <= StreamVideoCodec.MAX_CONFIG); csd = codecConfig
+                                    csd = mode.videoCodec.mergeConfig(csd, bytes)
                                 } else encoded(bytes, info, config, rotation, token)
                             }
                             if (info.flags and MediaCodec.BUFFER_FLAG_END_OF_STREAM != 0) problem = "unexpected encoder EOS"
diff --git a/tools/chatgui-android/app/src/main/java/com/utun/chat/data/StreamVideoCodec.kt b/tools/chatgui-android/app/src/main/java/com/utun/chat/data/StreamVideoCodec.kt
index 0d26b5f2..679f8aee 100644
--- a/tools/chatgui-android/app/src/main/java/com/utun/chat/data/StreamVideoCodec.kt
+++ b/tools/chatgui-android/app/src/main/java/com/utun/chat/data/StreamVideoCodec.kt
@@ -21,6 +21,17 @@ enum class StreamVideoCodec(val id: Int, val label: String, val mime: String, va
         require(bytes.isNotEmpty() && bytes.size <= H264AnnexB.MAX_FRAME)
         return if (annexB) H264AnnexB.normalize(bytes) else bytes.copyOf()
     }
+    /** Parameter sets могут прийти отдельными CODEC_CONFIG callbacks; сохраняем полный набор текущей revision. */
+    fun mergeConfig(previous: ByteArray, update: ByteArray): ByteArray {
+        val next = normalize(update)
+        val result = if (!annexB || previous.isEmpty()) next else {
+            val units = H264AnnexB.nals(previous).map { it.second }.toMutableList()
+            for ((_, unit) in H264AnnexB.nals(next)) if (units.none { it.contentEquals(unit) }) units += unit
+            units.fold(byteArrayOf()) { a, unit -> a + unit }
+        }
+        require(result.size <= MAX_CONFIG)
+        return result
+    }
     private fun nalTypes(bytes: ByteArray): Set<Int> = H264AnnexB.nals(bytes).map { (_, nal) ->
         val at = if (nal[2] == 1.toByte()) 3 else 4
         when (this) {
diff --git a/tools/chatgui-android/app/src/test/java/com/utun/chat/data/StreamVideoCodecTest.kt b/tools/chatgui-android/app/src/test/java/com/utun/chat/data/StreamVideoCodecTest.kt
index 5e27a8ec..6271c553 100644
--- a/tools/chatgui-android/app/src/test/java/com/utun/chat/data/StreamVideoCodecTest.kt
+++ b/tools/chatgui-android/app/src/test/java/com/utun/chat/data/StreamVideoCodecTest.kt
@@ -22,6 +22,13 @@ class StreamVideoCodecTest {
         val decoded = StreamVideoCodec.VP9.unpackKey(StreamVideoCodec.VP9.keyFrame(byteArrayOf(1), byteArrayOf()))
         assertTrue(decoded.first.isEmpty()); assertArrayEquals(byteArrayOf(1), decoded.second)
     }
+    @Test fun separateParameterSetsRemainCompleteWithoutDuplicates() {
+        val sps = nal(0x67, 1); val pps = nal(0x68, 2)
+        val config = StreamVideoCodec.H264.mergeConfig(sps, pps)
+        assertArrayEquals(sps + pps, config)
+        assertArrayEquals(config, StreamVideoCodec.H264.mergeConfig(config, sps))
+        StreamVideoCodec.H264.unpackKey(StreamVideoCodec.H264.keyFrame(nal(0x65, 3), config))
+    }
     @Test fun codecAndBitrateSurviveCameraModeSelection() {
         val base = StreamCaptureMode("a", 1280, 720, 30, 30, false, "encoder", 2_000_000)
         val hevc = base.copy(videoCodec = StreamVideoCodec.H265, minimumBitrate = 500000, maximumBitrate = 3000000)