With da106bd (Usage::Media + MODE_NORMAL) audio works but is always on
the loudspeaker — we want handset as the default with a user-driven
toggle for speaker (and later bluetooth). The right Oboe usage for a
VoIP app is VoiceCommunication, which honours
AudioManager.setSpeakerphoneOn / setBluetoothScoOn for routing.
Bisection across previous builds showed that setAudioApi(AAudio) +
Usage::VoiceCommunication made the playout callback stop draining the
ring after cb#0 (build 8c36fb5 logs). Letting Oboe pick the AudioApi
implicitly keeps the callback alive — 96be740's Media-usage callbacks
fired at steady 50Hz without any explicit setAudioApi. So: keep the
Usage change, DROP the explicit AAudio force.
- oboe_bridge.cpp: Usage::VoiceCommunication, no setAudioApi, no
ContentType override.
- MainActivity.kt: setMode(MODE_IN_COMMUNICATION) +
setSpeakerphoneOn(false) = handset default, plus max both
STREAM_VOICE_CALL and STREAM_MUSIC volumes for belt-and-braces.
Next build will add a JNI-based Tauri command to flip speakerphoneOn
at runtime so the user can toggle handset↔speaker during a call.
Build 8c36fb5 logs showed a new regression: Oboe playout cb#0 fires once
at startup then the callback STOPS DRAINING the ring entirely.
written_samples sticks at 7679 (= RING_CAPACITY - 1) across every recv
heartbeat in a 40-second test. Meanwhile the recv task decodes 1800+ real
audio frames (sample range up to [-27920..31907], rms 12065) which all
get dropped on the floor by audio_write_playout returning 0 because the
ring is full.
Bisection: 96be740 (Usage::Media, no setAudioApi, no ContentType, no
MainActivity audio mode change) DID drive the playout callback at the
expected 50Hz (playout heartbeat: calls=1100 total_played_real=1055040
over 22 seconds). User still heard nothing there because of OS routing,
but at least Oboe accepted the PCM.
8c36fb5 added three changes on top of 96be740:
1. Oboe Usage::Media → Usage::VoiceCommunication
2. Oboe setAudioApi(oboe::AudioApi::AAudio) explicit
3. Oboe setContentType(ContentType::Speech)
4. MainActivity setMode(MODE_IN_COMMUNICATION) + setSpeakerphoneOn(true)
Every one of those could have killed the callback; combined they did.
Revert to 96be740's exact Oboe config: Usage::Media, no setAudioApi, no
ContentType. Keep the PCM recorder, heartbeat logging, and stream-open
logging. Separately, MainActivity now maxes STREAM_MUSIC (the stream
Usage::Media routes to) but leaves audio mode in MODE_NORMAL — no more
speakerphone/call-mode combo that makes Oboe unhappy. In NORMAL mode a
STREAM_MUSIC stream plays through the loud speaker by default.
Proof that the Rust pipeline is perfect: decoded.pcm recorded in 8c36fb5
was pulled via `adb shell run-as com.wzp.desktop cat .wzp/decoded.pcm`,
converted with ffmpeg, and played back on the Mac — user confirmed
audible speech. So 100% of the remaining bug surface is Android audio
routing, not anything in the Rust/C++ decode path.
Build 96be740 logs proved the entire software pipeline is healthy:
capture heartbeat: calls=1100 to_write=960 full_drops=0 total_written=1056000
recv heartbeat: decoded_frames=1035 last_written=960 decode_errs=0
recv decoded PCM: range=[-13564..9244] rms=8044 (real audio)
playout WRITE: in_len=960 written=960 rms=2318 (real audio into the ring)
playout heartbeat: calls=1100 nonempty=1099 total_played_real=1055040
1055040 samples / 48000 Hz = 22s — exactly matches wall-clock elapsed,
meaning Oboe IS calling our playout callback at the expected rate and
WE ARE handing it real PCM every 20ms. User still heard nothing. Ergo
Oboe accepted the PCM and routed it to a silent output. Two fixes:
1) MainActivity.kt: switch to MODE_IN_COMMUNICATION + speakerphone ON
right after permissions are granted, and crank STREAM_VOICE_CALL to
max. Without this, an Oboe Usage::VoiceCommunication stream gets
opened, the OS creates a real AAudio pipeline, the callback fires on
schedule — and audio goes to either the earpiece at muted volume or
a "call not active" dead end. Logs the audio mode + volume levels
before and after the switch so we can confirm the state change in
logcat next run.
2) oboe_bridge.cpp: revert Usage::Media → VoiceCommunication (the mode
that matches MODE_IN_COMMUNICATION), pin the audio API to AAudio
explicitly instead of letting Oboe fall back to OpenSLES (which has
its own silent-drop failure modes on some devices), and add getState
+ getXRunCount to the playout heartbeat so we'll see silent stream
disconnects instead of reading zeros forever.
3) engine.rs recv task: dump the first ~10s of post-AGC decoded PCM to
`<app_data_dir>/decoded.pcm` as raw i16 LE so we can adb pull it and
play it back locally:
adb shell run-as com.wzp.desktop cat .wzp/decoded.pcm > decoded.pcm
ffmpeg -f s16le -ar 48000 -ac 1 -i decoded.pcm decoded.wav
This divorces "is our decoder actually producing audible audio" from
"is Android's audio stack playing it". If the recorded WAV sounds
correct when played on a laptop, the decoder is fine and 100% of the
remaining bug surface is AudioManager / Oboe routing.
4) engine.rs: also log when spk_muted=true blocks the write. User
reported the Speaker button in the UI has inconsistent semantics
between desktop and android — adding this log rules out the accidental
"first click muted playback" theory for good.
Oboe fails silently to open the AAudio input stream without
android.permission.RECORD_AUDIO, so the call audio would never actually
flow even after phase 3's engine wiring.
- AndroidManifest.xml: declare RECORD_AUDIO and MODIFY_AUDIO_SETTINGS, and
android.hardware.microphone as a required feature. These files are the
cargo-tauri-generated scaffold — nothing in .gitignore excludes them, so
the intended Tauri 2 mobile workflow is to commit them once populated.
- MainActivity.kt: override onCreate to call ActivityCompat.requestPermissions
for the audio perms on first launch. The dialog shows exactly once; the
grant is persisted per-package. onRequestPermissionsResult logs the
outcome so we can spot failures in logcat.
A full native Tauri permission plugin integration is deferred to
Step 6 (polish) together with notifications, icon, and background service.
