AEAudioFileWriter + NonInterleavedFloatStereo results in silent output
I have an app that currently uses TAAE with the
AEAudioStreamBasicDescriptionNonInterleaved16BitStereo audio description. It also has an export feature that uses
AEAudioFileWriter to export audio.
I'm trying to change the app to use
AEAudioStreamBasicDescriptionNonInterleavedFloatStereo instead to cut down on the number of converters that get added to the audio graph. Everything seems fine during normal usage of the app, but when I run an export, the audio file is the correct duration but is completely silent. This happens with both
kAudioFileWAVEType. It doesn't report any errors, just doesn't produce any sound.
Another possibly relevant point is that I'm exporting the audio using "offline" rendering - I stop the audio engine, then repeatedly render the top of the graph using this code: https://github.com/lijon/TheAmazingAudioEngine/commit/199181c1bb0b821e0b5129ebec5d80e50c3d4389.
Any ideas on why this is happening or how to fix it?