Fix: TRAX meter reflection — remove double attenuation from slider+loopback

Services/Audio/AudioGainProvider.cs

@@ -28,6 +28,8 @@ public sealed class AudioGainProvider
     /// <summary>Mic gain for the live mix (0 = muted).</summary>
     public double MicGain() => _micMuted() ? 0 : _micVolume();
 
-    /// <summary>Loopback (desktop/game) gain for the live mix (0 = muted).</summary>
-    public double LoopbackGain() => _gameMuted() ? 0 : _gameVolume();
+    /// <summary>Loopback (desktop/game) gain for the live mix (0 = muted, 1 = unity).
+    /// Unity because the slider now drives system volume via PushSystemVolume,
+    /// so the WASAPI loopback signal is already scaled by the user's volume choice.</summary>
+    public double LoopbackGain() => _gameMuted() ? 0 : 1.0;
 }

Services/Audio/AudioMixer.cs

@@ -10,8 +10,8 @@ namespace ytLive.Services.Audio;
 /// through the voice chain (bass → treble → noise gate → compressor), THEN
 /// level-metered and queued; loopback samples are resampled to 48 kHz stereo
 /// and queued. While live (<see cref="StartLive"/>), a 10 ms loop drains both
-/// queues, applies the honest gains (mic = MicVolume, loopback = GameAudioVolume
-/// × auto-duck when the mic is hot), mixes them to stereo float, runs the
+/// queues, applies the honest gains (mic = MicVolume, loopback = unity
+/// × auto-duck when the mic is hot — the slider drives system volume via mixes them to stereo float, runs the
 /// master limiter (a -1 dBFS ceiling so the sum never clips the encoder), and
 /// writes the chunk to the encoder's audio pipe.
 /// </summary>

ViewModels/MainViewModel.cs

@@ -652,7 +652,7 @@ public class MainViewModel : ViewModelBase
     /// Called whenever the game volume/mute change and on TRAX load.</summary>
     private void UpdateTraxLocalGain()
     {
-        _musicPlayer.LocalGain = GameMuted ? 0f : (float)(GameAudioVolume * 0.2);
+        _musicPlayer.LocalGain = GameMuted ? 0f : 1f;
     }
 
     private static void PushSystemVolume(double volume)
@@ -684,7 +684,7 @@ public class MainViewModel : ViewModelBase
     /// <summary>Displayed game meter level: 0 while muted; the volume position
     /// while the slider is dragged (or briefly after an unmute flash); otherwise
     /// the realtime live level scaled by volume.</summary>
-    private double GameMeterLevel => GameMuted ? 0 : _gameVolumeAdjusting || _gameVolumeFlash ? GameAudioVolume : Math.Min(1, AudioLevelMeter.ToDisplay((float)GameAudioLevel) * GameAudioVolume);
+    private double GameMeterLevel => GameMuted ? 0 : _gameVolumeAdjusting || _gameVolumeFlash ? GameAudioVolume : Math.Min(1, AudioLevelMeter.ToDisplay((float)GameAudioLevel));
 
     public double GameMeterFillWidth => GameMeterLevel * 288;
 

ai.md

@@ -447,10 +447,11 @@ devices, no timers).
   (mp3/wav/m4a) → `VolumeWaveProvider16` at the hardcoded **0.20** bed (no slider) → `WaveOutEvent` on
   the default device, **looping on any clean natural end** (`PlaybackStopped` with `e.Exception == null`
   → rewind + replay; the earlier `Position >= Length` check was unreliable for `MediaFoundationReader`
-  and let tracks play once then stop). The desktop/game bar scales it locally via `LocalGain` (the VM's
-  `UpdateTraxLocalGain` runs on every `GameAudioVolume`/`GameMuted` change and on TRAX load), so the
-  creator **hears** the game volume slider and mute work on the music in the headphones — matching the
-  stream, where it rides the loopback channel ducked with the game. No third mixer input. The footer
+  and let tracks play once then stop). The desktop/game bar's mute toggles `LocalGain` (0 or 1;
+  `UpdateTraxLocalGain` runs on every `GameMuted` change and on TRAX load), so muting kills TRAX
+  in the headphones — matching the stream, where it rides the loopback channel. The volume slider
+  drives system volume (`PushSystemVolume`), which scales the entire loopback signal including
+  TRAX — one knob controls everything. No third mixer input. The footer
   **TRAX** button lives **inside the game audio bar** (in the preview overlay), **left of the
   "Desktop Audio" label** (the creator's pick — it rides the desktop channel, so the music control
   sits with the desktop audio controls): status dot (**red** no track / **yellow** loaded stopped /
@@ -469,8 +470,9 @@ devices, no timers).
   silently falling back to the default endpoint.**
 - **Game audio bar** (desktop/game, **always visible** — TASK 4's `IGameAudioDetector` show/hide gating was **removed 2026-08-15**: the bar used to appear only while a full-screen game with sound was up, which kept hiding the creator's desktop meter; the detector stack is gone, desktop audio is just automatic WASAPI loopback): overlaid **at the bottom of the preview window** (bottom-center, dark translucent
   chip, a mirror of the mic bar: meter + mute + volume slider). It's monitoring UI **in the preview
-  grid** — the meter is display-only, but its **volume slider + mute are stream-honest** (via
-  `AudioGainProvider.LoopbackGain`) **and drive TRAX locally** (`MusicPlayer.LocalGain`). Relabelled
+  grid** — the meter is display-only, but its **volume slider drives system volume** (`PushSystemVolume`
+  scales the entire WASAPI endpoint, so both the live headphones and the loopback capture reflect the
+  slider) **and mute kills TRAX** (`MusicPlayer.LocalGain` = 0). Relabelled
   **"Desktop Audio"** (TASK 8) since TRAX rides the same channel.
 - **`WaveToFloat`** (pure, shared): WASAPI mix formats → interleaved float — IEEE float 32-bit direct,
   PCM 16-bit normalized to -1..1, `WaveFormatExtensible` with the IEEE-float subformat GUID