Sometimes I need to edit segments out of one of my DVDs and I don't have the original files handy. I can import the VOB files directly into Vegas but there is usually an audio offset, such that there is a slight delay to the sound. I can fix it manually of course but it is a laborious process. Is there some easy workaround, or do I have to use some other editor like Womble Video Wizard?

These are DVDs I have made using AC3 stereo. I edit using Vegas and author the DVDs with DVD-A.