CS feels wrong...keyboard lag?

[Johnny Girth]

Alright guys. I always seem to have this problem with CS: Source. I have an ifra-red wireless keyboard/mouse (Microsoft) which work perfectly in windows. There is absolutely no lag whatsoever and they're extremely responsive.

However in CS it feels like I'm on an ice-skating rink. There seems to be a delay when I press any of the movement keys and it just feels like I'm sliding about everywhere.

Any idea what's wrong with it?

 

[Johnny Girth]

SP2 installed but not hearing any trippy sounds. Everybody who's ever played on my PC notices it as well!

Rest of system is Opteron 146 @ 2.8ghz, X800XT grahics, 1GB ram.

Very confused!