In my office, three of the editors on three separate systems have experienced the same occasional music track problem. During extensive editing in a project, an .aiff music track is perfectly timed. At some point -- usually after a render -- the opening of the music track will suddenly get thrown off. For example, a song clip suddenly starts in the middle of a song instead of the beginning. From that point on, we normally have to re-edit the song into the track by setting new in and outs on the track, although sometimes reconnecting the track to the source file will work. Also seems to happen when we have multiple audio tracks and have worked on the project for awhile.
The music tracks we use are all from a music library and some are 44.000 Khz. Could that affect things? Since it only happens occasionally, seems like that's probably not the root cause. We're hoping the answer isn't mixing down the audio because in many instances, we're still working on the tracks individually.
Rendering a Mixdown of all the audio in a sequence is no big deal, minutes at most and often just seconds. Also, it's the only way to properly hear the actual line-up and levels of fresh work, the way it's going to be heard in a final render.
Thanks very much for the response. We'll convert and mixdown more I suppose. Just strange we haven't had any other offset/synch issues on final output without doing that before. But if it will help this issue, I'll gladly do it.