If it does it with ONE or TWO mp3s then I would say its a mp3 problem. If its all of them either they were majorly jacked when they were ripped or you are burning them wrong. What burning app are you trying? If it is corrupt mp3s, Matridom is right on when he says to convert them to wavs. Be ready for a large loss in HD space. A wav can be 10-20(!) times as large as an mp3.