I'd try using the optical cable on your DVD player first. If it's still there then try an analog rca cable. As your PS2 isn't doing it, it might just be a setting in your DVD player, have you tried playing with the PCM/Bitstream setting? On another thought, what connection are you using for video?
Hi-Def Format Neutral
Samsung BD-1400, PS3 40GB
Toshiba HD-A2, HD-XA2 & XBox 360 HD DVD