How do you release an MTAudioProcessingTap?

Question

The header file for MTAudioProcessingTap says that its initialization and prepare callbacks will be balanced by unprepare and finalize callbacks. However, in Apple\'s exampl

Answer 1

I had the same problem. To make it work, I had to reset the player item's audioMix, the tap processor (MYAudioTapProcessor in Apple's sample project) and manually release the MTAudioProcessingTapRef:

MTAudioProcessingTapRef tap = ((AVMutableAudioMixInputParameters *)_audioTapProcessor.audioMix.inputParameters[0]).audioTapProcessor;
_player.currentItem.audioMix = nil;
_audioTapProcessor = nil;
CFRelease(tap);

This causes the finalize callback to be invoked.

Edit: Seems like the CFRelease is not required, see comments.