AudioQueueOutputCallback buffer data (during playback and recording)

Question

I have trouble with understanding what exactly is in buffer containing incoming data. Is AudioQueueBufferRef refers to piece of data (from last callback call) or it is whole past data (since AudioQueue start) ?

Answer 1

Have you taken a look at the Apple developer documentation for this?

An audio queue buffer, newly available to fill because the playback audio queue has acquired its contents.

It also provides the queue that triggered the callback.