[QUOTE=Anita;217826]
  • Only a few of my dvds do this
  • during certain parts of play


DVD disks are played with constant linear velocity. Or in other words, they spin the disk faster when they're reading the outside tracks and slow them down when they're reading the middle. This explains why it only happens during some times.

The other point has already been explained by everyone else. When your tires are unbalanced or warped, your steering wheel vibrates. Similarly, when your DVDs are unbalanced, they vibrate while spinning. Some of your disks must be better balanced than others. First, make sure there aren't any stickers on the disk that would throw it out of balance. Other than that, I don't think there's much more you can do.