Thanks you for very nice library :)
I found a bug about FLAC.
So I report it to you.(Sorry about my poor English.)
I think,format of stream that is in output scope and whose element is zero is from the currently-active output audio hardware.
So we cannot change its format and return kAudioUnitErr_PropertyNotWritable.
This error affect changing another stream format.
Thanks you for very nice library :) I found a bug about FLAC. So I report it to you.(Sorry about my poor English.)
I think,format of stream that is in output scope and whose element is zero is from the currently-active output audio hardware. So we cannot change its format and return kAudioUnitErr_PropertyNotWritable. This error affect changing another stream format.
Please look the section,”Essential Characteristics of I/O Units”. (https://developer.apple.com/library/ios/documentation/MusicAudio/Conceptual/AudioUnitHostingGuide_iOS/AudioUnitHostingFundamentals/AudioUnitHostingFundamentals.html)