All of a sudden, when I watch a DVD, the picture has wavy lines running through it. I'm using the S-Video input. I tried using the component inputs with the same problem. I tried a different player and still have the same problem. It's not the DVD itself because the wavy lines show up even without a disc in the player. The DVI input works just fine with my DirectTV box plugged into it. Any ideas as to what is causing the interference?