help! presence knob??

[porkchop]

Alright so I have a studio 22 and for some reason the presence knob makes a crackling sound when turned, and the presence seems to cut in and out.

Example: presence is turned from 2 to 3, and gets really high, then turned a little more and seems to get cut out and the sound is bassy.

Is there anything I can do to fix this myself? I called a guitar amplifier repair shop and they were going to charge $85 just to diagnose the problem. Thanks all.

 

[Boogiebabies]

It sounds like the pot is bad. I have replaced about 6 of these over the years. They usually get banged in and the 4 prongs that hold the pot open up and mess the sweep of the pot up. You can try to pry them back on carefully. If you tighten them with pliers, do not go too far or the pot wont turn at all. If it's totally broke, call Mesa with the part number of the pot and have them send you one. The number is on the housing.