When you created this, did you have to do anything particular with the audio in FCP (or whatever editor you were using)?
You could try adding a compression marker either side of the section in the FCP timeline, then go from there to Compressor to create the MPEG2 asset, then use that as your DVD content... I am thinking there may be an issue with your encode, which a specific set of compression markers may help to resolve.
But this is just guesswork at the moment :-/
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lafcpug mod