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AUAudioFilePlayer priming for compressed files

For ExtAudioFile/CAAudioFile you can "trick" the AudioConverter into making compressed file reads sample accurate by seeking back a few mp3-sized frames and throwing away the samples up to your desired start point. I'd love to get this working with the AudioFilePlayer AU, as trying to chop up compressed files and play them back in order does not work. But since the AudioFilePlayer does all the seeking/ reading for you, I can't tell if this is possible. I saw the kAudioUnitProperty_ScheduledFilePrime property but no docs for it other than to set it to default. Is there a way to "prime" the file player AU a few frames in the past before scheduling?

We currently do this the long way, using MovieAudioExtraction into an ABL for ScheduledSoundPlayer. We have to start decoding from 0 to be sample accurate in QT's MAE-- an enormous waste of CPU when you're trying to get 0.3s of audio out near the end of a 10m track. AudioFile was better for mp3s-- you only had to go a few frames back, not all the way to the beginning. So we'd love to shoehorn that into AudioFilePlayer and chuck all of the manual management of IO and PCM ram.

-Brian


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