Thanks for the response Chris. My post audio guy couldn’t open the file in Pro Tools.
In FCP I could see that it was only processing track 1 and then stopping. Normally you can see it go through track 2,3,4,5 etc..
I just went in and trashed some extraneous tracks, and enabled some clips that were disabled before, and it seemed to export all tracks this time. I’m sending to post audio now. Fingers crossed!
Although it seems to have worked this time, I’d still like to know if there are any good reasons why this might have been a problem to begin with..
8core MacPro, 3.0 GHZ, 10GB RAM, OSX 10.5.6