I am playing Call of Duty Black ops which is an awsome game btw But when I do play it I am using IDT sound and?

sometimes not all the time my sound will glitch and go out or skip a little and at the same time that happens my game itself glitches and legs just a little is it the sound that im using causing this problem maybe my sound car needs to be updated because I have 2gb of ram and the game calls for 2 to and I called the best buy geek squad and they think it has to do with my ram what do you think ? Thanks.