When I open the file the audio and video start at the same point, but while the audio plays at normal speed, the video is accelerated. I tried mucking around with the Track Synchronization but that only changes the audio's starting point rather than its speed. It is definitely the video playing too fast rather than the audio too slow, too.
The file in question is one in a folder of thirteen and is the only one which has this problem.
Has anyone come across this before?