iOS: error finding/initializing AQDefaultDevice

I’m having some issues with audio not starting properly on iOS, although I’m not getting an error from AudioDeviceManager::initialise. It happens occasionally. I’ve tried moving the call to initialise audio later as I read that such errors can sometimes occur if the app is seen by iOS as still being in the background.

I’ve only seen this in the simulator, although I’ve not done much testing on a real device.

Example console output:

[AudioHAL_Client] AudioHardware.cpp:875:AudioObjectAddPropertyListenerBlock:  AudioObjectAddPropertyListenerBlock: no object with given ID 0
[DDAgg] DefaultDeviceAggregate.cpp:737:BuildAggregate: Error finding valid input or output devices!
[AudioHAL_Client] AudioHardware.cpp:2692:AudioDeviceStop:  AudioDeviceStop: no device with given ID
[AudioHAL_Client] AudioHardware.cpp:2692:AudioDeviceStop:  AudioDeviceStop: no device with given ID
[aqme] 318: error -66680 finding/initializing AQDefaultDevice
[aqme] 318: error -66680 finding/initializing AQDefaultDevice
108: * * * NULL AQIONode object
[aqme] 318: error -66680 finding/initializing AQDefaultDevice
771: Can't make UISound Renderer
[aurioc] 1029: failed: -10851 (enable 3, outf< 2 ch,  44100 Hz, Int16, inter> inf< 2 ch,  44100 Hz, Int16, inter>)