audio synch problem VOB to MPG

[ajmsnr]

Trying to convert an VOB file to an MPG so I can watch it using quicktime on my Mac. Most of the time it works fine, however for some files the audio is about 5-10 seconds behind the video. The settings that work most of the time are the defaults:
Codec AAC
Bit rate 96
Sampling 48000
Channels Stereo
Mode CBR

If I try other Codec the files are unplayable. Any suggestions on getting the timing correct?

[Case]

Did you check the duration of the source file with the duration of the output audio and output video? I'm asking, because most often with sync issues, it is the audio that is fine and it is the video that drifts. If that is indeed the case, then your audio details are mostly irrelevant.