[carp_audio_package] error in iOS when app in background

[sc00n]

I get an error when I use AudioSamplingPackage.NOISE from carp_audio_package 0.30.1 in my sampling scheme.

The app runs fine when in foreground. When the app is in background, I get the following error after a while:

flutter: [CAMS DEBUG] Writing data point to file - type: dk.cachet.carp.activity
[aurioc] AURemoteIO.cpp:1600:Start: AUIOClient_StartIO failed (561145187)
[avae]            AVAEInternal.h:109   [AVAudioEngineGraph.mm:1545:Start: (err = PerformCommand(*ioNode, kAUStartIO, NULL, 0)): error 561145187
audio_streamer/SwiftAudioStreamerPlugin.swift:82: Fatal error: 'try!' expression unexpectedly raised an error: Error Domain=com.apple.coreaudio.avfaudio Code=561145187 "(null)" UserInfo={failed call=err = PerformCommand(*ioNode, kAUStartIO, NULL, 0)}
audio_streamer/SwiftAudioStreamerPlugin.swift:82: Fatal error: 'try!' expression unexpectedly raised an error: Error Domain=com.apple.coreaudio.avfaudio Code=561145187 "(null)" UserInfo={failed call=err = PerformCommand(*ioNode, kAUStartIO, NULL, 0)}
* thread #1, queue = 'com.apple.main-thread', stop reason = Fatal error: 'try!' expression unexpectedly raised an error: Error Domain=com.apple.coreaudio.avfaudio Code=561145187 "(null)" UserInfo={failed call=err = PerformCommand(*ioNode, kAUStartIO, NULL, 0)}
    frame #0: 0x000000019ca0eeac libswiftCore.dylib`_swift_runtime_on_report
libswiftCore.dylib`_swift_runtime_on_report:
->  0x19ca0eeac <+0>: ret    
libswiftCore.dylib`_swift_reportToDebugger:
    0x19ca0eeb0 <+0>: b      0x19ca0eeac               ; _swift_runtime_on_report
libswiftCore.dylib`_swift_shouldReportFatalErrorsToDebugger:
    0x19ca0eeb4 <+0>: adrp   x8, 337468
    0x19ca0eeb8 <+4>: ldrb   w0, [x8, #0x299]

After this error, the app stops. When I only use other CARP packages (e.g. from context, device and sensor), the app keeps working, also in background.

I added everything to plist that should be there according to carp_audio_package.

Thank you for your help!

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