AAX - wrong playHead position when recording

Hi all,

I’m experiencing some strange behavior of the AudioPlayHead::PositionInfo when recording - on Pro Tools / AAX only.

(note: “position values” below refers to timeInSeconds, lastBarStartPpq, positionPpq, and timeInSamples)

Starting at time 0:00 (beginning of session) in Pro Tools:

  • when I play without recording, it seems the first block is a few samples (it varies from 32 to a few 100s) before 0:00 - strange but ok, all position values seem to match, all at a negative value
  • when I record, only about 50% of the time, I get two extra blocks with 0 as position values but still isPlaying set to true. Then on the 3rd block I get the same as when not recording (negative values for all position values)

My biggest problem here is that the DAW tells me it’s playing while the position is set to 0… And then goes negative >_<
I am not sure how to handle this, it clearly needs a special hack for AAX since other DAWs will set all position values to zero and set isPlaying to true when starting playback at the beginning of the session, and that would be perfectly normal.

Thanks for some insights :slight_smile:

Naaah - nevermind, I spoke too fast: isPlaying was not set to true, only isRecording.

That’s still a nice warning if someone finds this thread: Pro Tools seems to run two buffer first where isRecording is true, isPlaying is false, with all positions set to zero, and then the actual playing starts (with isPlaying set to true).