QT export out of sync

Hi all,

I am desperately seeking a solution to the following problem.

I have a large Final Cut Pro project that I have been working on for six months. Recently I attempted to export a couple of 50-minute sequences as QuickTime movies. I am using standard 1080i HDV presets for timelines and exporting in the same flavor. The problem is that the audio goes terribly out of sync in the export. It gets progressively worse so that it is obviously out of sync by mid way through the program. Also, I noticed that the final duration of the exported file is one or two seconds short of exactly 50 minutes, even though the timeline is exactly 50 minutes. I have not had any problems doing this basic procedure in the past but now nothing seems to work. What I have done so far is:

trashed all video and audio render files and re-rendered everything
performed audio mixdowns on all sequences prior to render
deleted all FCP preference files, cache, etc.

I even took all of the firewire media drives to a different computer (MacBook Pro) and performed the export on an entirely different system with the same results.

Can anyone please shed any light on why my audio is still out of sync in my QT exports? I feel trapped here and dont know what to do next....


thanks,

Sterling

QT version 7.4.1
FCP version 6.0.2 I think
Mac 10.4.11

Sterling Noren
Owner/Writer/Producer/Editor
WideWorld HD Productions
Seattle, WA