[Gary Nelson] "All of our work is NTSC Apple Prores 422 (29.97)
and our audio is at 48k 16 bit (and perhaps 24bit, don't know if that matters...) "
Audio at 16bit is most likely the cause of your issue, FCP wants 48K 24bit audio.
Try a Mixdown of your audio and you will find that it should clear things up.
( this is my 6th post about audio errors when using 16bit audio in the last couple of days- it is the issue)
gary adcock
Studio37
HD & Film Consultation
Post and Production Workflows for the Digitally Inclined
Chicago, IL
http://blogs.creativecow.net/24640
