The capture stream opened under AAudio's default VoiceRecognition input
preset, which deliberately bypasses the HAL's acoustic echo canceller —
so a phone playing the game audio out of its own speaker fed that audio
straight back to the host. Two layers fix it, both behind a new "Echo
cancellation" setting (default ON, next to the Microphone toggle in the
touch and console settings, per-profile like every tier-P setting):
- Native: the mic opens under the VoiceCommunication preset (HAL AEC/NS
on the capture path) and allocates an audio session id. The open
ladder is Exclusive+voice → Shared+voice → Exclusive → Shared — some
HALs refuse the preset or a session id outright, and a mic without
echo cancellation still beats no mic; the last rungs are exactly the
preset-less open this always did.
- Kotlin backstop: nativeStartMic now returns the allocated session id
(0 = none), and StreamScreen hangs the Java AcousticEchoCanceler +
NoiseSuppressor off it (guarded by isAvailable), releasing them on
every mic-stop path — the surface teardown and the final dispose — so
a surface recreate re-attaches instead of leaking effect engines.
The playback stream is untouched: retagging it voice/communication
would route it through the phone-call chain and regress quality.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
enricobuehlerandClaude Fable 5
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