It may not be dirt, but spraying some De-ox it and working the knob for a minute is an easy thing to try. I suppose you'd be sure it was dirt if it made some noise when you adjusted it quickly while monitoring the channel.

One channel of my Sytek MPX-4Aii drops actual signal drastically when increasing the gain knob at certain points. Fairly certain It's not a dirty pot. Any idea what might be causing this and what can be done to fix it? The problem channel is a standard op amp rather than Burr Brown.

Don't spray deoxit into any pot fyi. I believe the pots are Noble brand, but you could contact sytek (I think he's still accepting some emails) for the best cleaner if any. You can try to exercise the pot a bit back and forth over scratchy or intermittent points (with the mute on).Theirs tend to have a lot of gain in a small bit of travel at the top of the range. That's normal. Outside of the last 15% of travel, it should be pretty smooth. If you're turning up the level and signal drops, you might need to replace it or try exercising.

Is it a stepped pot? Mine has all stepped pots.

japmn wrote:Is it a stepped pot? Mine has all stepped pots.Ditto.

numberthirty wrote:japmn wrote:Is it a stepped pot? Mine has all stepped pots.Ditto.It's a detented pot, which is still a pot with some native lube. This, as opposed to a rotary switch which you can use contact cleaners on.

For conductive plastic faders and pots, that might be ok. I'm not certain his are. He was a fan of carbon pots.

I thought this stuff was ok... no?

Whoops. I guess I'm the bad advice guy here. Now I'm trying to remember if Deox It has made its way to the pots on my Sytek. Hmmmmm.I suppose too many people on the web swear by that stuff for everything, maybe a bit more application specifics than I knew of. Thanks for checking in Greg.

Thanks folks...I seemed to have worked out the offending dirt.