New set up and lots of noise

recently upgraded from Cubase 5 to Cubase 6.
New PC windows 7
intel i5 processor
6 gb ram
using cl1 interface

upped my buffer to 1500+ (seems too much) to attempt to eliminate crackles and pops.
still getting crackles and pops although not as much.

Shouldn’t be a computer problem becasue I made sure I exceeded all requirements.

Crackles/pops not audible at source but are showing up in playback.

Also get crackels when starting and stopping playback.

know it must sound a bit crude…but I am at a loss for trouble shooting. would someone be kind enough to start me in the right direction please.

Sounds like some device driver is having ill behaviour. This one may help you: