What to do with erratic level knob?

[snackmaster]

I’m having some trouble with the level knob on my mk 2 Octatrack. Suddenly, it’s impossible to dial things in because the knob just wildly moves up and down, making it nearly impossible to write music on the unit.

It’s the only knob that does this–any advice on how to fix this?

[sezare56]

Encoders change value on their own

If you do this, make sure to use a control cleaner, not a contact cleaner like Deoxit D5. Control cleaner also lubricates and is safe for pots and encoders. Contact cleaner doesn’t lubricate, and will actually wash the existing lubrication out of your pots/encoders, which can make them feel bad, wear faster, or if you’re unlucky completely seize up and stop turning (that last one’s not so likely with encoders). This is the best way to clean an encoder but it’s also a lot more work and a bit …

[snackmaster]

Hey, this is very helpful. Is there a control cleaner that is recommended?

I found this one: https://a.co/d/gLBLgyE

Do you think that one is suitable? Or, is there a better product?

[sezare56]

@snackmaster

Is there a control cleaner that is recommended?

Probably, I have an old one but I don’t know what is the best for encoders.
@Supercolor_T-120, @darenager, @shigginpit…

[Supercolor_T-120]

I do know you don’t want to spray any kind of control cleaner into an encoder - encoders aren’t pots and the process for cleaning them is different, and unfortunately harder. If you spray cleaner in it you might see a little improvement but probably not much if at all, and you could damage the encoder depending on what type it is and what cleaner you use.

I don’t know of a video specifically about cleaning OCtatrack encoders, but this one about replacing one has good footage of what to expect inside:

Octatrack Encoder Repair

This one shows how to open and clean the encoder on an Akai S5000. It’s the best one I know of off the top of my head, and was my reference when I had to clean the encoder on my own s5000:

Akai S5000 Sampler DATA knob / rotary encoder fix - SIMPLETHINGSTOYS

The big difference is that the Octatrack encoders have push switches where the S5000 doesn’t, so they’re a bit different inside but the principle is the same. Hopefully between the two you can sort it out. If you or a friend are comfortable with it, replacing might actually be easier than cleaning. The Bourns PEC16-4020F-S0024 encoder is still cheap and easy to get - there’s even a working Mouser link in the description on that first video.

Opening it up and cleaning it took about 15 minutes (I was being extra careful, so it took a lot longer than it really needed to) but it worked really well - when I got it in 2018 the encoder skipped and jittered so much it was barely usable. 15 mintues carefully opening, cleaning and relubricating completely eliminated all of the issues, and it still works perfectly today.