24p - 23.976 fps video & 24 fps audio

[SZE]

Hi

I am starting the sound edit on a film shot on the Canon 5D. The film was shot at video speed 23.976 fps, with the sound shot seperately at 24 fps.

As the Canon 5D has no way of receiving external TC or audio feeds (from what I understand), sound has to be re-sync in post using the clapperboard.

I have been brought onto the project at a stage when the sound rushes have already been loaded into Final Cut Pro 7, and sync up to clapperboard and the reference audio there is from the Canon 5D built-in mic.

The problem picture department are having (I am yet to receive any material) is that the sound rushes start off in sync, but slowly start to drift out of sync (running longer), to a degree that after 5 minutes or so you are looking at over 2 frames difference.

I am assuming that at the stage the sound rushes were imported into Final Cut Pro some kind of automatic pull-up / pull-down should have been carried out, but unfortunately it hasn't so this will need to be fixed by us in sound post.

I would be very grateful if anyone can give me a quick breakdown of the usual 24p HD workflow, and if anyone has ny suggestions about how the 24 fps sound rushes can be fixed, and hopefully automatically converted/processed upon import into Pro Tools HD.

Thanks in advance