diff --git a/tools/chatgui/CMakeLists.txt b/tools/chatgui/CMakeLists.txt
index bb81c750..02146ae4 100644
--- a/tools/chatgui/CMakeLists.txt
+++ b/tools/chatgui/CMakeLists.txt
@@ -518,6 +518,12 @@ endif()
 add_test(NAME test_stream_view COMMAND test_stream_view)
 set_tests_properties(test_stream_view PROPERTIES TIMEOUT 30 ENVIRONMENT "QT_QPA_PLATFORM=offscreen")
 
+add_executable(test_stream_audio tests/test_stream_audio.cpp)
+target_include_directories(test_stream_audio PRIVATE ${UTUN_INCLUDE_DIRS})
+target_link_libraries(test_stream_audio PRIVATE utun_voice utun pthread ${CMAKE_DL_LIBS})
+add_test(NAME test_stream_audio COMMAND test_stream_audio)
+set_tests_properties(test_stream_audio PROPERTIES TIMEOUT 30)
+
 target_link_libraries(test_ptt_key_chord PRIVATE ${QT_CORE})
 add_test(NAME test_ptt_key_chord COMMAND test_ptt_key_chord)
 
diff --git a/tools/chatgui/tests/test_stream_audio.cpp b/tools/chatgui/tests/test_stream_audio.cpp
new file mode 100644
index 00000000..8a6b0e60
--- /dev/null
+++ b/tools/chatgui/tests/test_stream_audio.cpp
@@ -0,0 +1,87 @@
+/* Реальный stereo Opus/SoundTouch: высота тонов, баланс каналов и отображение услышанных кадров в исходный PTS. */
+#include <cmath>
+#include <cstdio>
+#include <cstdlib>
+#include <vector>
+
+extern "C" {
+#include "../../../lib/debug_config.h"
+#include "../../../lib/mem.h"
+#include "../../../lib/opus_codec.h"
+#include "../../../src/stream/stream_playback_audio.h"
+}
+
+#define CHECK(x) do { if (!(x)) { DEBUG_ERROR(DEBUG_CATEGORY_STREAM, "stream audio test line=%d: %s", __LINE__, #x); exit(1); } } while (0)
+
+static void test_stereo_tempo() {
+    auto* encoder = opus_codec_encoder_create(48000, 2);
+    CHECK(encoder && opus_codec_encoder_application_set(encoder, OPUS_CODEC_APP_AUDIO) == 0);
+    CHECK(opus_codec_encoder_bitrate_set(encoder, 128000) == 0);
+    auto* audio = stream_playback_audio_create(0); CHECK(audio);
+    stream_playback_audio_set_tempo(audio, 1100);
+    std::vector<int16_t> decoded;
+    int16_t pcm[1920], output[1920]; uint8_t packet[1275];
+    for (unsigned frame = 0; frame < 200; frame++) {
+        for (unsigned i = 0; i < 960; i++) {
+            double t = (frame * 960 + i) / 48000.0;
+            pcm[2 * i] = (int16_t)std::lrint(10000 * std::sin(2 * 3.141592653589793 * 1000 * t));
+            pcm[2 * i + 1] = (int16_t)std::lrint(4000 * std::sin(2 * 3.141592653589793 * 500 * t));
+        }
+        int length = opus_codec_encode(encoder, pcm, 960, packet, sizeof(packet)); CHECK(length > 0);
+        CHECK(stream_playback_audio_feed(audio, frame * 20000, packet, (size_t)length) == 0);
+        for (;;) {
+            int count = stream_playback_audio_pull(audio, output, 480, INT64_MAX); CHECK(count >= 0);
+            if (!count) break;
+            decoded.insert(decoded.end(), output, output + count * 2);
+        }
+    }
+    stream_playback_audio_finish(audio);
+    for (unsigned i = 0; !stream_playback_audio_empty(audio) && i < 100; i++) {
+        int count = stream_playback_audio_pull(audio, output, 480, INT64_MAX); CHECK(count > 0);
+        decoded.insert(decoded.end(), output, output + count * 2);
+    }
+    CHECK(stream_playback_audio_empty(audio));
+    uint64_t written = stream_playback_audio_written(audio);
+    CHECK(written == decoded.size() / 2 && std::abs((double)written - 192000 / 1.1) < 2);
+    unsigned crossings[2] = {0, 0}; double energy[2] = {0, 0};
+    unsigned first = 9600, last = (unsigned)written - 9600;
+    for (unsigned i = first + 1; i < last; i++) for (unsigned ch = 0; ch < 2; ch++) {
+        if (decoded[(i - 1) * 2 + ch] < 0 && decoded[i * 2 + ch] >= 0) crossings[ch]++;
+        energy[ch] += (double)decoded[i * 2 + ch] * decoded[i * 2 + ch];
+    }
+    double seconds = (last - first) / 48000.0;
+    CHECK(std::abs(crossings[0] / seconds - 1000) < 5 && std::abs(crossings[1] / seconds - 500) < 5);
+    CHECK(std::sqrt(energy[0] / energy[1]) > 2.0 && std::sqrt(energy[0] / energy[1]) < 3.0);
+    int64_t half = stream_playback_audio_position(audio, written / 2);
+    CHECK(std::abs(half - (int64_t)(written / 2 * 1100000.0 / 48000)) < 100);
+    int64_t gain = stream_playback_audio_pending_gain(audio, written / 2);
+    CHECK(gain > 170000 && gain < 190000);
+    stream_playback_audio_destroy(audio); opus_codec_encoder_destroy(encoder);
+    DEBUG_INFO(DEBUG_CATEGORY_STREAM, "[PASS] stereo x1.1: unchanged tone pitch/balance, exact duration and heard PTS mapping");
+}
+
+static void test_silence_clock() {
+    auto* encoder = opus_codec_encoder_create(48000, 2); auto* audio = stream_playback_audio_create(1000000);
+    CHECK(encoder && audio);
+    int16_t pcm[1920] = {0}, out[1920]; uint8_t packet[1275];
+    for (unsigned i = 0; i < 4; i++) {
+        int length = opus_codec_encode(encoder, pcm, 960, packet, sizeof(packet)); CHECK(length > 0);
+        CHECK(stream_playback_audio_feed(audio, 1000000 + i * 20000, packet, (size_t)length) == 0);
+    }
+    int got = stream_playback_audio_pull(audio, out, 960, INT64_MAX); CHECK(got > 0);
+    uint64_t before = stream_playback_audio_written(audio);
+    int64_t pts = stream_playback_audio_position(audio, before);
+    stream_playback_audio_silence(audio, 9600);
+    CHECK(stream_playback_audio_position(audio, before + 4800) == pts);
+    CHECK(stream_playback_audio_starved(audio, before + 4800));
+    CHECK(stream_playback_audio_pending_gain(audio, before + 4800) == 0);
+    stream_playback_audio_destroy(audio); opus_codec_encoder_destroy(encoder);
+    DEBUG_INFO(DEBUG_CATEGORY_STREAM, "[PASS] device silence freezes source time and preserves stereo decoder state");
+}
+
+int main() {
+    debug_config_init(); debug_set_level(DEBUG_LEVEL_ERROR); debug_set_category_level(DEBUG_CATEGORY_STREAM, DEBUG_LEVEL_INFO);
+    size_t allocations = u_get_allocated_count();
+    test_stereo_tempo(); test_silence_clock(); CHECK(u_get_allocated_count() == allocations);
+    return 0;
+}