Welcome to forum dc3. The first thing that comes to mind is make sure you use the best media. You didnt mention whether you were playing this on standalone dvd player, if you were some of the older ones wont play it perfect sometimes. I used dvdfab once & I had distortion problem too. Quit using it. Just went on to something else.
Didnt want the hassles. It seems to work fine for a lot of people though.