Is there then another way to play the audio track of a video file? Having the audio and video in one file is handy because it allows the video author to handle the sync when Pd is just doing the playback. I am working with a student, Ardis Kadiu, on a 9-screen, 9-computer system and we need to be able to play the author's movies with sound and all in sync.

For basic sync playback with no further processing Quicktime does pretty well. It is important to note that the audio played by Quicktime does not run through the PD audio chain at all. That becomes a sticky point when adding this feature.