Audio sync problems in TMPGEnc DVD Author when using VOB files

[marknyc5]

I use DVD Author to make DVDs of movies I've burned off TV with my standalone DVD recorder. I like to make them directly from the VOB files to avoid re-encoding.

But in my latest project, the audio gets out of sync by the end of the film. How can that happen when I'm working from the VOB files, with no conversion to MPEG, etc.? And how can I fix it?

Thanks for any help,

Mark