DVD player picture freezes

Question

I've had this same problem with 4 different DVD players. When playing a disc sometimes the picture (and sound) will stop. Then it'll start for a few frames and stop again. Then sometimes it will jump ahead and play a bit and freeze again. Sometimes it will then go ahead and play for a couple minutes before freezing again. The first and third players were Wal-Mart units. The second was a Sony from Circuit City. I now have a Pioneer and hooked it up and it does the same thing. I've been using a HDMI cable for the connection. It seems strange that ALL the players do the same thing. Any ideas?