TASK 24 post-pause polish batch (creator's 8 review issues, 2026-08-15): (1) desktop/game audio volume slider + (2) mute were no-ops — the AudioMixer's gain Func seams defaulted to unity because the VM never passed them; new AudioGainProvider (Services/Audio/) wires MicMuted/MicVolume/GameMuted/GameAudioVolume into the mixer at construction, read live each mix tick, so sliders and mutes are stream-honest; the game bar also scales TRAX locally via new MusicPlayer.LocalGain (UpdateTraxLocalGain on every game volume/mute change + on load) so the creator HEARS the controls work on the music in the headphones. (3) TRAX played once then stopped — OnPlaybackStopped only looped on Position>=Length (unreliable for MediaFoundationReader); now any clean stop rewinds + replays, errors/explicit stops surface via PlaybackEnded; unused using dropped. (4+6) TRAX moved right of Socials in the footer's left cluster (centered under scenes/sources); the mic cluster is now MIC + meter + mute + volume. (5) mic source persists — LayoutStore gains a Settings key/value table (SaveMicSourceName/LoadMicSourceName); the VM saves on pick and restores before the mixer's first Start, so a restart reconnects the same vetted device (green) or reports it missing (yellow). (7) Backdrop's missing trashcan shifted the edit/eye icons right — new HiddenBoolToVisibilityConverter keeps the trash column reserved (Hidden, not Collapsed) so every source row's icons stay in fixed columns. (8) a 1px hairline with top/bottom padding separates scenes from sources in the left panel. Docs in the same commit: ai.md (gains honest + drive TRAX locally, TRAX loops, mic persistence, footer layout), TASKS.md TASK 24, HANDOFF.md shipped state, ViewModels/index.md. ONE integration test: AudioPipelineTests.Mix_HonorsProviderGains_AndGameMute_KillsTheLoopback (real mixer + provider gains through the pipe harness: scaled loopback audible, silence after mute). Build 0 warnings, 197 tests passing

Services/LayoutStore.cs

@@ -135,6 +135,12 @@ public class LayoutStore : IDisposable
                 IsEnabled INTEGER NOT NULL DEFAULT 0
             );
             """,
+            """
+            CREATE TABLE IF NOT EXISTS Settings (
+                Key TEXT PRIMARY KEY,
+                Value TEXT NOT NULL
+            );
+            """,
         };
         foreach (var sql in statements)
         {
@@ -585,6 +591,30 @@ public class LayoutStore : IDisposable
         return scenes;
     }
 
+    /// <summary>The last picked mic source name, or null if never chosen. Restored
+    /// at startup so the sound bar reconnects to the same, already-vetted device.</summary>
+    public string? LoadMicSourceName()
+    {
+        using var cmd = _connection.CreateCommand();
+        cmd.CommandText = "SELECT Value FROM Settings WHERE Key = 'MicSourceName';";
+        var value = cmd.ExecuteScalar() as string;
+        return string.IsNullOrWhiteSpace(value) ? null : value;
+    }
+
+    public void SaveMicSourceName(string? name)
+    {
+        using var cmd = _connection.CreateCommand();
+        cmd.CommandText = "DELETE FROM Settings WHERE Key = 'MicSourceName';";
+        cmd.ExecuteNonQuery();
+        if (string.IsNullOrWhiteSpace(name))
+            return;
+
+        using var insert = _connection.CreateCommand();
+        insert.CommandText = "INSERT INTO Settings (Key, Value) VALUES ('MicSourceName', $name);";
+        insert.Parameters.AddWithValue("$name", name);
+        insert.ExecuteNonQuery();
+    }
+
     public void Save(IEnumerable<Scene> scenes, Webcam? webcam, SocialsConfig? socials, Music? music = null)
     {
         using var tx = _connection.BeginTransaction();