Are you doing other things with your computer while your having this problem? If your maxing out you systems resources while trying to play a file it can result in poor quality playback. Also while encoding and burning files to a disc, it's best not to be doing other things with your cpu. It's also better to burn videos at lower speeds for better reliability.

Look up the files with Bitzi before downloading to help sort out the bad ones. Also preview files when they get to 15%.

Tips on d/loading files in this thread: How to find music(and movies)

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