Just encountered a version of this problem, myself. After synching six channels of mono track to my DSLR .mov files for almost a week (without issue), Premiere 5.5.0 crashed on me. Upon re-starting the program, none of the mono .wav files would play audio in my merged clips. In fact, the waveforms for each separate track seems to have been “wiped” clean. They are simply dead tracks, now. Oddly, the stereo camera track (which was automatically split to two mono tracks when I merged the clip) is still working fine and dandy… too bad I have practically no use for it.
I’ve tried deleting the media cache and re-conforming the files. I’ve tried re-labeling the files, and starting with the files offline before re-linking in Premiere… nothing is bringing back my audio. It looks like I may have lost a whole lot of work.
Having reconciled myself to re-synching all of my footage, I’m now looking for a vote of confidence that it won’t happen again. I updated to version 5.5.2, which will hopefully have addressed the problem. But I’m still not feeling terribly confident in Premiere, and am nervous about using it to re-synch all of my footage. Does anyone have any new insight into this issue? Anyone know if the 5.5.2 update addressed the bug? I would really appreciate any advice!