I agree with Francksoy and abrown15 - that it is a media problem. That is unless you're also doing all sorts of strange things on your computer WHILE burning. You can prove this to yourself using CloneDVD2 (a great pgm) by keeping the temp files and playing them from the hard drive. If they play without glitches then it's a "burner/media" problem. If the files on the harddrive show problems -- well let's hope they don't.