Recording won't resume if the app is in background and a call is taken

[sergi-labhouse]

Package version
6.1.1

Environment

• OS: iOS

Describe the bug

If you start a recording and the app is in foreground, receiving a call pauses the recording, but the recording resumes automatically after the call ends.

If you start a recording and put the app in background, receiving a call pauses the recording, but the recording never resumes after the call ends.

Add your record configuration RecordConfig(encoder: encoder, numChannels: 1, audioInterruption: AudioInterruptionMode.pauseResume);

To Reproduce

Steps to reproduce the behavior:

1. Take the sample app
2. Add audioInterruption: AudioInterruptionMode.pauseResume to RecordConfig in Recorder._start()
3. Run the app in iOS
4. Start a recording
5. Put the app in background
6. Take a call or FaceTime
7. End the call.
8. Put the app in foreground

Although RecorderSessionExtension.onAudioSessionInterruption() and AudioRecordingDelegate.resume() are being called, the recording doesn't resume

Expected behavior

After the call ends, the recording automatically resumes, as it does when the app is in the foreground

Additional context

PoC.zip

[Anderzzon]

I don't know if this is related, but when a call is interrupted in background, no file path is returned when you then put the app in foreground and stop the recording.

[llfbandit]

Thanks for the report.

I don't find any good conditions to check resume case on my device (I don't have SIM card and, well I'm not an experienced user on iPhones...).
Each time I play a sound, .shouldResume is false...

Anyway, I pushed an attempt to fix this: origin/feature/interrupt
@sergi-labhouse Are you able to check it there?

@Anderzzon If you are sure that the recording isn't stopped by the plugin itself, please fill a separate issue. Otherwise, it a normal case as you didn't call the stop method from the app. Finally, the path is always what you gave to the plugin.

[Anderzzon]

I tried to listen to interruption events with the audio_session library and then manually tried to resume the recording without success. So I’m wondering if this is a limitation by iOS?

[llfbandit]

The fix attempts to force activation of audio session. While in background the guess is that the system shut it down.

[sergi-labhouse]

Hi @llfbandit thanks for the fix.
I can confirm that this worked, after adding IosAudioCategoryOption.mixWithOthers and IosAudioCategoryOption.duckOthers, to the IosRecordigConfig.
The final config for the example project looks like this:

const config = RecordConfig(
            encoder: encoder,
            numChannels: 1,
            audioInterruption: AudioInterruptionMode.pauseResume,
            iosConfig: IosRecordConfig(
              categoryOptions: [
                IosAudioCategoryOption.defaultToSpeaker,
                IosAudioCategoryOption.allowBluetooth,
                IosAudioCategoryOption.allowBluetoothA2DP,
                IosAudioCategoryOption.mixWithOthers,
                IosAudioCategoryOption.duckOthers,
              ],
            ));

[llfbandit]

Thanks for the feedback.
So, the fix with both category options mixWithOthers and duckOthers are needed to make this work?

[sergi-labhouse]

Yes, without those I still had the same issues.
FYI, I was getting this error: NSError domain: "NSOSStatusErrorDomain" - code: 560557684 0x0000000114e16ee0 when executing try AVAudioSession.sharedInstance().setActive(true).

As explained here, the fix was to add those categories

[llfbandit]

Ok, thanks for the clarification.

[gabrieluca]

@sergi-labhouse
@llfbandit

Can you guys share your whole configuration that solved this issue?
Because I followed the instructions and it still does not work for me.
Every time the app is in background and there is another session (play a video, receive/answer a call), it always stops the audio afterwards.
It shows this log: AVAudioSessionInterruptionOptions(rawValue: 1) right before stopping.

Environment
iOS 18.7.1
iPhone 16 Pro

  RecordConfig config = RecordConfig(
    audioInterruption: AudioInterruptionMode.pauseResume,
    iosConfig: const IosRecordConfig(
      categoryOptions: [
        IosAudioCategoryOption.defaultToSpeaker,
        IosAudioCategoryOption.allowBluetooth,
        IosAudioCategoryOption.allowBluetoothA2DP,
        IosAudioCategoryOption.mixWithOthers,
        IosAudioCategoryOption.duckOthers,
      ],
    ),
    encoder: currentCodec,
    bitRate: 64000,
    numChannels: 1,
    device: inputDevice,
  );

<key>UIBackgroundModes</key>
<array>
	<string>audio</string>
	<string>fetch</string>
</array>