Emu XL-7 & MP-7 User's Group

Hi all
Sorry for off topic post but could do with a quick answer to a problem 
with a Virus C.
Getting some loud pops and clicks with the audio.
I think its a problem with the FX engine.
Can anyone tell me if they get zipper noise when they increase or 
decrease the delay time? or do they get a smooth glitch free transition?
Also sometimes i get a loud click if i turn the delay time down to 0 
then the same increasing it.
The same goes for the send knob, but only occasionally. 
Somethings not right but ive not got another one to compare it against.
Cheers guys
Gonz