Using AVAudioSession overrideOutput to speaker causes WebRTC to malfunction

[Jun711]

I am using @saghul AudioRoute and also this plugin to set up a WebRTC p2p call. I have encountered this problem recently.

To reproduce this problem:

1. Set up an active WebRTC call.
2. Toggle the speaker on then off(overrideOutput to speaker).
3. GSM call interrupts the current WebRTC call (accept / reject).
4. WebRTC call loses audio.

It doesn't happen if I don't toggle the speaker. Fyi, I have tried to listen to AVAudioSessionInterruption event and reset the audio but to no avail. Just wonder if anyone has seen the same problem.

[saghul]

Do you lose the override or do you lose audio completely?

[Jun711]

I lost the audio completely so I don't know if I lost the override too.

1. make the AVAudioSession to listen for AVAudioSessionInterruption event and set the AVAudioSession to inactive when there is an incoming interruption. And, when the interruption is over, set it back to active again.
2. make the AVAudioSession to listen for AVAudioSessionInterruption event and set the AVAudioSession override to default when there is an incoming call.

I wonder if you have the same issue too, @saghul . Thank you!

[ibc]

I wonder if you have the same issue too, @saghul .

Others may also reply.

[saghul]

The problem is that libwebrtc (which this plugin is based on) assumed nobody else was changing the AVAudioSession configuration other than itself, until M59.

Once we update the library, all those problems will (hopefully) go away, but it's not an easy feat.

[saghul]

Oh, and no, we have no ETA for when the update will happen.

[hthetiot]

The problem is that libwebrtc (which this plugin is based on) assumed nobody else was changing the AVAudioSession configuration other than itself, until M59.

Once we update the library, all those problems will (hopefully) go away, but it's not an easy feat.

[hthetiot]

I will implement AVAudioSession.interruptionNotification here

• https://github.com/cordova-rtc/cordova-plugin-iosrtc/blob/task/libwebrtc-update-m69/src/PluginRTCAudioController.swift#L64

Will be fixed via #399 on 6.0.0

[hthetiot]

Related: https://bugs.chromium.org/p/webrtc/issues/detail?id=8126#c35

[hthetiot]

This works.

cordova plugin add cordova-plugin-background-mode

 // Enable Background audio
          if (cordova && cordova.plugins && cordova.plugins.backgroundMode) {
              cordova.plugins.backgroundMode.enable();
          }