The webcam's frames reach the compositor later than the mic's samples reach the audio
pipe, so the voice runs ahead of the lips. The existing lip-sync offset could not fix
that: it delays the WHOLE mix, which drags desktop and alert audio — neither of which
has a camera to follow — out of sync in the process.
So the delay line learned channels (mono for a source, stereo for the mix, offset always
in milliseconds so the frame count is what stays constant), and FillAndMix runs a second
line over micChunk before the mix. Slider-side: presets off / 150 / 200 in the LIP-SYNC
bay under the whole-mix control, persisted as Audio.MicSyncOffsetMs.
Default 175 ms is the creator's own number for a C920 pipeline (they asked for
+150..+200). It is a setting, not a constant, because the right figure belongs to the
camera and the machine — a faster camera wants less, no camera wants none.
Both delay lines are reconfigured every tick, so the 2026-09-12 trap still applies and is
documented at both sites: a Configure that reallocates discards the buffered voice every
10 ms.
673 pass, 0 warnings. Ear check pending: this is an audio change.
Creator ruling (2026-10-30): TRAX is background music and is controlled separately from desktop and
mic — so KISS it:
- TRAX loses its own ladder and slider. It is one number plus ±5 dB buttons, disabled at the ends
(−60 dB floor, +6 dB ceiling).
- It STARTS at −50 dB, taken from the creator's own meter readings, and moves in 5 dB clicks. If that
proves inaudible on their setup, six clicks lands at −20 — the buttons exist for exactly that, and
`TraxDefaultDb` is one constant.
- Layout follows: Desktop's volume now sits directly beneath its ladder, and the TRAX row (name,
play/pause, level) sits beneath that, inside the GAME bay. The bays are MIC | GAME+TRAX | LIP-SYNC.
- The metering tap on the player stays (it is how "is the music producing sound" is answered) but has
no ladder of its own; the desktop bed already shows the music.
Guards updated: TraxBayTests now asserts the stepper wiring and that the row has NO SegmentMeter;
GameBayTests asserts the desktop fader sits below the desktop ladder.
Unit 8. Re-houses the shipped TASK 22 offset in the dock:
- slider −200…+200 ms, snapping to 5 ms ticks (the existing property still clamps and persists)
- readable readout: "0 ms (aligned)" when right, signed otherwise ("+50 ms", "−120 ms")
- presets 0 / +50 / +100; 0 IS the detent — a button is easier to hit than a snap, and "the lip-sync
is right" deserves one click.
Guard: SyncBayTests pins the binding, the readout, the presets and the snapping, and that the
offset stays the persisted property (no second source of truth).
Unit 7. The bay shows the track name (left-click toggles playback, right-click opens the picker —
the label stays the control), a play/pause button, the duck badge, and a dB level.
No ladder here, deliberately: nothing measures the music bed, and a decorative ladder would break
the measured-not-painted rule. A test asserts the bay has no SegmentMeter.
The level is real: `ITraxPlayer.UserGain` is a new creator gain multiplied onto the fixed design
volume, separate from `LocalGain` (which follows the desktop mute). The VM's `TraxVolumeDb` is the
same dB scale as the other faders, so unity means the bed's design level.
Unit 5. The dock's first working bay:
- 24-segment ladder fed by `MicMeterFraction` — the MEASURED display level (already scaled by the
volume and zeroed when muted), never the gain setting.
- Fader in dB via `MicVolumeDb` (−60 … +6, 0 = unity) with a mono-weight readout
(`MicVolumeDbLabel`), so "−6.0 dB" is what the creator reads instead of "0.50".
- Mute button whose dot uses the existing MicStatusBrush; clicking the device name opens the mic
picker, so the label stays the control (the KISS rule: one place to change the mic).
The preview's own mic row stays for now — it is removed in the final unit, after the dock bays are
complete, so nothing is lost if a bay misbehaves.
Guard: MicBayTests — the bay binds the dB face and the measured level (not the gain), the fader
range IS the scale's range, the VM surface exists, and mute still zeroes the ladder.
Unit 4 of the sound-bar refactor. `Controls/AudioDock` takes the bottom row that held the empty
`BottomBar` spacer (deleted): four bay containers (MIC / GAME / TRAX / LIP-SYNC) above a 36px
master strip, all token-styled.
Height comes from `Models/AudioDockLayout`, not from a setting: 168px normally, 36px below a 900px
window height. At the 1366×768 minimum a full dock leaves ~398px for the preview, so the collapse
is mandatory, not cosmetic. The dock listens to its window's SizeChanged and re-applies.
Nothing here pretends to be a meter yet — the bays and the master readouts fill in over the next
units, each with its own test.
Guard: AudioDockLayoutTests pins both sides of the threshold (768 collapsed, 1040 expanded), the
boundary itself, and the two heights as the design's numbers.
gramps