I just bought a brand new dvd burner and was playing a dvd on my computer and about every 2 min everything freezes, lags for about 3 seconds, then begins to play normally again. Can anyone give me some help on what the problem could be.

my system specs are...
processor - P4 3.0
Motherboard - Asus p4c800-e Deluxe
Ram - 1 Gig corsair XMS Extreme (PC 3200)
Vid Card - MSI Ge-force 5900fx
HD - maxator 7200rpm 200 gig (sata)
DVD burner - Plextor PX-712SA (sata)
PS - Antec true power 430 watt

Also it wouldent be because of a overheating problem, i have a koolance watercooled case and the processor reaches a max of 31 celsius. Thanks in advance for any help.