Wave 1 gave the Android client a mic worth using. It gave it no way to stop
talking: leaving the stream, or digging through Settings to turn the whole
feature off, were the only ways to stop the room being heard. Now a tap (or
Select + Y on a pad) mutes it, and the screen says so while it lasts.
How muting gates the capture, and why that way. The AAudio input stream is
never stopped: a stop/start would re-run the input-preset fallback ladder and
re-prime the buffers on every toggle — hundreds of milliseconds, and possibly
a landing on a different rung, silently losing the HAL echo canceller wave 1
went to some trouble to get. Instead the encode loop reads an AtomicBool per
10 ms frame and, while it is set, drains the frame out of its ring and drops
it there — the last point before it would have become an Opus packet. Nothing
is encoded, nothing is sent, and the realtime capture callback is untouched,
so its allocation-free discipline and the queue policy stay exactly as wave 1
verified them. A toggle costs one atomic store and takes effect on the next
10 ms boundary.
The frame counter keeps advancing across a mute, because it numbers the
captured 10 ms TIMELINE rather than the datagrams. The gap the host then sees
is exactly the audio that never came: its de-jitter conceals at most a few
frames of it before the pump's 600 ms stale-gap flush resets the chain
outright, which is the right reading of a mute. Encoding silence instead
would have kept a pointless uplink and a host-side ring alive for its whole
duration.
Mute is per session and nothing is persisted — a new stream always starts
unmuted, and no new setting exists. The flag lives on the session handle
rather than on the capture, so the mic stop/start a surface recreate performs
brings the user's choice back with it, with no window in which the fresh
capture could send an unmuted frame.
The control is offered on the evidence that a capture is actually running
(nativeMicActive), not on the setting: with the mic disabled, RECORD_AUDIO
denied, or every AAudio input rung refused, there is nothing on screen to
lie about. On touch it is a pill in the corner the stats HUD doesn't use —
the one in-stream control, so it sits above the gesture layer to take its own
taps — dim while live, a red "Muted" badge while it isn't. On TV that badge
is the indicator alone: Select + Y is the control there, and a focusable
button would fight the game for the D-pad. Y is deliberately not one of the
exit chord's buttons, so neither chord can be reached through the other.
One honest consequence of keeping the stream open: the platform's recording
indicator stays lit while muted, because the mic really is still open. What
stops is the encode and the send.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
enricobuehlerandClaude Fable 5
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