Audio captured separately to recorder, drifting - I'm losing hair.

So a multicam show I'm editing was supposed to be sending all the final sound to the cameras and then have the mixer record to files as backup. Well, of course, they just kept all the final sound on the recorder and just recorded on camera sound on each of the cameras - so now I have to sync it all up. I have slates to sync to - the project was shot SD 24p on the HVX to miniDV tapes. I've captured into FCP 7.0 and have my cameras all synced up. Now I'm bringing in my post sound (in WAV files) and matching it up to the tapes in a 29.97 timeline (it's for broadcast). My final WAV audio sound files drift progressively more and more throughout the clip and the mixed final WAV sound files gets further and further behind my picture. In the TC rate of the WAV files while in FCP, it lists them at 24 fps which I know audio doesn't work on a frame rate but wasn't sure what else to check. How the hell do I fix this?

Thanks in advance...

FCP 7
24p SD footage from HVX captured with the NTSC DV easy setup preset
Editing on a 29.97 timeline (no render bars on top, it's correct).
OSX 10.5.8
Intel 3ghz quad, 12 gigs Ram

FCP / AVID EDITOR
Features : Television
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