I bought two songs and they both skip. Help?

Almost a week ago I bought two songs from Itunes using a gift card and they downloaded perfectly fine. The second I went to listen to one, at first, everything was fine but then it skipped like a minute of a four minute song. The second song only plays two minutes of a five minute song. I've already re-downloaded the new Itunes software AND the songs but it's still ****** up. Any suggestions?