diff --git a/tools/chatgui/ffmpeg/build_ffmpeg.sh b/tools/chatgui/ffmpeg/build_ffmpeg.sh
index 78206df2..8448a670 100755
--- a/tools/chatgui/ffmpeg/build_ffmpeg.sh
+++ b/tools/chatgui/ffmpeg/build_ffmpeg.sh
@@ -7,7 +7,7 @@ SRC_DIR="$BUILD_DIR/src"
 INSTALL_DIR="$BUILD_DIR/install"
 JOBS=$(nproc 2>/dev/null || echo 4)
 AMF_HEADERS_VERSION="${AMF_HEADERS_VERSION:-1.5.3}"
-FFMPEG_PROFILE_MARKER="$INSTALL_DIR/share/utun-chatgui-ffmpeg-minimal-v3"
+FFMPEG_PROFILE_MARKER="$INSTALL_DIR/share/utun-chatgui-ffmpeg-minimal-v4"
 
 case "$(uname -s)" in
     Linux)                      PLATFORM=linux ;;
@@ -64,6 +64,7 @@ check_cmd nasm
 check_cmd pkg-config
 check_cmd git
 check_cmd curl
+check_cmd patch
 
 # ============================================================================
 # Step 1: Codec libraries (static .a, built with -fPIC)
@@ -229,6 +230,11 @@ if [ ! -d "$FFMPEG_SRC" ]; then
 fi
 
 cd "$SRC_DIR/ffmpeg"
+AMF_QP_PATCH="$SCRIPT_DIR/patches/ffmpeg-7.1.2-amf-live-qp.patch"
+if ! grep -q 'utun_qp_applied' libavcodec/amfenc.c; then
+    log "Apply live AMF QP ceiling support..."
+    patch --batch --forward -p1 < "$AMF_QP_PATCH" || die "Failed to apply live AMF QP ceiling patch"
+fi
 log "Configure FFmpeg..."
 
 CONFIGURE_ARGS=(
diff --git a/tools/chatgui/tests/test_stream_publish.cpp b/tools/chatgui/tests/test_stream_publish.cpp
index dc7530ac..8590ffd9 100644
--- a/tools/chatgui/tests/test_stream_publish.cpp
+++ b/tools/chatgui/tests/test_stream_publish.cpp
@@ -4,6 +4,7 @@
 #include <QTimer>
 #include <QLabel>
 #include <QComboBox>
+#include <QSpinBox>
 #include <QCheckBox>
 #include <QButtonGroup>
 #include <QPushButton>
@@ -22,6 +23,7 @@
 #include <pthread.h>
 #endif
 #include "../src/live_video_encoder.h"
+#include "../src/stream_qp_control.h"
 #include "../src/stream_publish_engine.h"
 #include "../src/stream_publish_window.h"
 #include "../src/sound_manager.h"
@@ -257,6 +259,8 @@ private slots:
             boxes[1]->setCurrentIndex(boxes[1]->count() - 1); // Меньший размер сохраняется при повторном открытии.
             selectedMode = boxes[1]->currentData().toList();
             boxes[3]->setCurrentIndex(boxes[3]->findData(4000000));
+            controls.findChild<QSpinBox*>("streamMaxQp")->setValue(25);
+            controls.findChild<QCheckBox*>("streamAdaptiveQp")->setChecked(true);
             controls.findChild<QButtonGroup*>()->button(270)->click();
             controls.findChildren<QCheckBox*>().first()->setChecked(false);
             if (boxes[2]->count() > 1) boxes[2]->setCurrentIndex(boxes[2]->count() - 1);
@@ -268,6 +272,7 @@ private slots:
         QCOMPARE(stored.value("bitrate").toInt(), 4000000); QCOMPARE(stored.value("rotation").toInt(), 270);
         QVERIFY(!stored.value("audio").toBool());
         QVERIFY(!stored.value("show_cursor").toBool(true));
+        QCOMPARE(stored.value("max_qp").toInt(), 25); QVERIFY(stored.value("adaptive_qp").toBool());
         StreamPublishEngine reopenedEngine;
         StreamPublishWindow reopened(&reopenedEngine, group, nullptr, saved);
         QSignalSpy changes(&reopened, &StreamPublishWindow::settingsChanged);
@@ -275,6 +280,8 @@ private slots:
         auto boxes = reopened.findChildren<QComboBox*>();
         QCOMPARE(boxes[1]->currentData().toList(), selectedMode);
         QCOMPARE(boxes[3]->currentData().toInt(), 4000000);
+        QCOMPARE(reopened.findChild<QSpinBox*>("streamMaxQp")->value(), 25);
+        QVERIFY(reopened.findChild<QCheckBox*>("streamAdaptiveQp")->isChecked());
         if (StreamPublishEngine::supported()) QTRY_COMPARE(boxes[2]->currentData().toInt(), stored.value("codec").toInt());
         QCOMPARE(reopened.findChild<QButtonGroup*>()->checkedId(), 270);
         QVERIFY(!reopened.findChildren<QCheckBox*>().first()->isChecked());
@@ -287,6 +294,21 @@ private slots:
         StreamPublishWindow restoredAuto(&reopenedEngine, group, nullptr, automatic);
         QCOMPARE(restoredAuto.findChildren<QComboBox*>()[3]->currentIndex(), 0);
     }
+    void qpAdaptationFollowsBitrateWithoutSpikes() {
+        StreamQpControl qp; qp.reset(28, 1000000, true, 0);
+        QCOMPARE(qp.update(1000000, 1000000), 28); // До двух секунд одиночный KEY не меняет потолок.
+        QCOMPARE(qp.update(0, 2000000), 29);
+        QCOMPARE(qp.update(1000000, 4000000), 30); // Не более одного пункта за интервал.
+        for (int64_t now = 6000000; now <= 12000000; now += 2000000) qp.update(250000, now);
+        QCOMPARE(qp.limit(), 31); // Сглаживание не дёргает QP около целевого битрейта.
+        for (int64_t now = 14000000; now <= 30000000; now += 2000000) qp.update(10000, now);
+        QCOMPARE(qp.limit(), 28); // Возвращаем выбранный потолок, не снижаем его дальше.
+        qp.reset(28, 1000000, false, 0); QCOMPARE(qp.update(10000000, 2000000), 28);
+        qp.reset(50, 1000000, true, 0);
+        QCOMPARE(qp.update(1000000, 2000000), 51); QCOMPARE(qp.update(1000000, 4000000), 51);
+        qp.reset(24, 4000000, true, 10000000);
+        QCOMPARE(qp.update(1000, 11000000), 24); QCOMPARE(qp.bitrate(), uint64_t(0));
+    }
     void proportionalScreenModes_data() {
         QTest::addColumn<QSize>("source"); QTest::addColumn<QSize>("maximum"); QTest::addColumn<QSize>("reduced");
         QTest::newRow("full-hd") << QSize(1920, 1080) << QSize(1920, 1080) << QSize(1280, 720);