I have a problem with my vci.
anytime I want to change an effect by holding Shift und turning the 4. effect knob the music starts getting slower and I hear crackles and so. The CPU-usage stays at about 30 %. The knob itself works fine, when I change the effect ammount, the problem starts only in combination with Shift. The other knobs + Shift work perfectly.
I think you need to use a contact cleaner for these such as Caigs.. you can find it in almost any electronic shop. I had a problem with my “hi” EQ, in the software (both Traktor and VDJ) the display would show the the knob bouncing around even though I was not twisting the actual knob. Shot some Caigs in there and twisted it back and forth and left it over night. The knob is good as new and it does not bounce in either software.
Probably just a small piece of dust in there.. it will do it.. my right jog had that problem and it was fixed by lightly blowing the disc and the optical reader.