Already erased memory card
Same problem, but I already erased the memory card on which my video was saved. I uploaded the video to iMovie and saw the thumbnails pop up, and so assumed that everything was fine; then, I needed the memory space on the card in order to tape something else.
Imagine my surprise when I went back to watch the video and it was 2x too fast for the audio.
Any way I can fix it? Or am I doomed to watch the video forevermore at 2x speed with the audio out of sync?