[A6] Knobs not working right.

[QualityTunage at aol.com]

I've had my A6 for 4 months and it has suddenly developed an annoying 
problem. When I try to adjust various knobs there is a delay before they work. Up 
until now there has been a delay of no more than a few seconds, which I can live 
with, but last night I was tweaking the cut off for about 3 - 4 minutes before 
it suddenly jumped into life! It seems to do this on every patch that I 
audition too. I have the latest OS, and I haven't changed any important settings. 
Is this a common problem, and if so is there an easy solution? Up to now I have 
found the overall sound of the A6 to be lovely, but I find the manual and the 
OS to be a little lacking. Many thanks,

Coz.