Scratchy pot on PreSonus FP10

[scubaninja]

Hi everyone,

I have a scratchy volume pot on my PreSonus FP10, and I was wondering if anyone here could offer some advice on how to clean it?

The "Main" volume knob is scratchy. However, you can only hear the scratchy sound when sound is playing through the interface and the volume is being adjusted at the same time. With no music playback, the knob is silent when you change the volume.

Is this a cleaning issue? Is this more like my "crackle OK" Zvex pedal and nothing to worry about? The headphone volume knob doesn't do this.

[brandondrury]

I'm interested to know this one, too, as I have some pots that need some work. My patented technique of twisting them a million times in 3 seconds doesn't seem to be doing me any good.

[scubaninja]

I tried the low tech approach of taking the knob off and blowing on it. That used to work for Nintendo cartridges, right?

A million years ago my (now ex) girlfriend's dad helped me with a scratchy input connector on my old Mackie 1202 (not VLZ, the original one from 1993 or so). He had an electronics hobby, and sprayed something directly into the noisy 1/4" or RCA jacks (can't remember now). If memory serves correctly, he said it was called color TV cleaner, or something to that effect, and that it was good for all sorts of stuff. Could this be similar to what he was using?

Also, even if that did work on a purely analog console, something tells me it's not such a good idea to just spray that into my Firewire sound interface and hope for the best.

I sort of feel like an ignoramus. I never personally did the maintenance on any of the live sound systems I mixed on, so this aspect of it is new to me.

[venuestudio]

TV tuner cleaner is the best way to clean pots. There is Techspray's Blue Shower that is a cleaner and degreaser. Open up the unit, spray liberally in the pot. exercise the pot back and forth as you spray. Don't be afraid to drowned it, you will not hurt it. Let dry and you will be good to go.

[scubaninja]

TV tuner cleaner is the best way to clean pots...

I just looked at your web site. It says you have eight years of live sound experience and an EE degree? It sounds like you were more than qualified to answer this question

Thanks!

[venuestudio]

I have been a tech for 30+ years and have cleaned at least a couple of pots over the years! The Blue Shower should be the ticket.

[scubaninja]

Here are some links to the products being discussed:

TV Tuner / Contact Cleaner (Hosa)
Amazon.com: Hosa D5S-6 Deoxit Contact Cleaner 5% Spray: Musical Instruments

Techspray Blue Shower
Techspray 1667-8S | Degreasers/Solvents

[scubaninja]

OK, so I ordered the Hosa D5S-6 Deoxit Contact Cleaner (free shipping with Amazon Prime) and gave it a try.

It worked!

The scratchiness is completely gone. I didn't even disassemble the unit or anything, I just took the knob off and sprayed it in (while it was unplugged, of course).

One thing I noticed is that now the volume knob that I sprayed the contact cleaner in twists MUCH more easily than all of the other 10 knobs on the unit. I almost wonder if PreSonus put some sort of grease in there to make the knobs seem more substantial.

At any rate, it's back to fully functional, which is what I cared about. And I still have plenty left over to fix any other similar problems that pop up with this, or any other piece of equipment.

Thanks to everyone, especially venuestudio, for all the help!

[venuestudio]

Glad to hear everything is in working order again.