Hi all.
I have been trying to track down a fault on my 101 for some time now and am at a loss as to wear the problem lies

The VCF-ENV slider doesn't work, which considerably irritates me!
I have had the machine open and checked for bad joints, tested the pot itself, but have found no apparent issues.
Does anyone with any experience have any idea where I should be looking? I really want to get things sorted, but can't afford to send her off to get fixed

Help much appreciated!!!
James.