“Scratchy” again/level controls on Mackie Active Monitors. Advice?

Usually a quick turn or two fixes the issue. In the past, on other volume controls I’ve sprayed a little Detoxit D5 and had good results. I’m a bit hesitant in this case due to the built in amplification. Any ideas? I’ve heard of some people even using WD40 or Blaster. Any help really appreciated. Thanks.

 

Meant “gain” control.

 

I would be hesitant because of the built-in...speakers. You want the shaft pointing straight up for best fluid penetration to the potentiometer innards, which means laying the speaker on its front - but - you don't want your cleaner dripping through the plate amp on to the back side of the speaker drivers (although the potential for damage is minimal, really).

The amp itself - I've hosed them down with half a can of contact cleaner, no worries there (unclear if any DeoxIT spray actually contains any real lubricant that may be left behind).

Position the speaker face down, in a way that the drivers are protected if they protrude from the front. You can usually pull off the plate amp removing about 10 screws. Leave unplugged for a hour first for safety. Then pull up the amp and put a towel inside or suspended across the bottom under the amp, and lay it back down. Then you can dose away with the knob removed and turn the shaft with your fingers until you feel the difference. Wipe away mess on the front.

Deoxit Fader is the only one recommended for conductive plastics - which is how the fader is made in modern potentiometers, while D5 is the only one to "deoxidize" corrosion, likely not the problem.

My theory is that the worn-away carbon builds up in the vaseline-like lube and causes the crackle as particles pass under the contacts. Rinse that out and you are good.

 

I like the idea of using WD40 as a cleaner, and have had great luck with it.
Clean the pot with it first, let it dry, then use DeOxit. I always have the D5 and the F5 on hand.
A lot of people cuss and carry on about WD40, yet I think it's wonderful stuff and fairly cheap too.
I've heard some people use compressed air for potentiometers, but I've never tried using it, never had to.
Could be the pots have corroded also and may need replacing.
Mackie can abe touch and go with their quality in my opinion.