I have an Alembic Strat set, with added 3-way Q, installed on a guitar I put together (Warmoth Flame Koa over Black Limba body/ Modulus graphite neck).   It's been my number one for several years.  Recently, it has developed a high-pitched, low volume whine, especially if the volume and filter are full open, the equivalent of the 10 position.  Thoughts?

Bill, tgo

First though is exercising the controls.  I had that happen on a series bass, exercised the controls a couple hundred times each and the noise went away.  That said, it may be something different going on with your guitar.  

Any new sources of interference near you? Seems like I recently heard y'all moved upstate. 🤔

Could it be described as high frequency RF? If so, we do have an upgrade available for that circuit that you can do yourself. 

I had a high pitched whine on my S1 guitar for a while and found one of the culprits was powerline ethernet adaptors. I used round the home.

I doubt it's RF interference as it has happened in several different locations.   I get the squeal when the guitar volume is turned  up relatively high, (I like to play with it set at "10" and use a volume pedal at the end of the chain), and the filter is full open, at the "10" position.   If I turn the filter down to about "8", the squeal goes away, but seems to come back at less volume when the filter gets to about "4" or less.  It's very high pitched, some people hear it better me, some don't hear it at all.  I did try exercising the volume and filter pots about 200 turns, each.  That maybe helped a little.  I've been playing this guitar without this issue for many years.

Bill, tgo

I wonder if it's the squeal i got when i bought my series I bass that happened near the fully open position of the filter knob. I took it to the father of forum member Geepee, and he had a look at it and squirted some contact cleaner into the pot, Bingo! Not suggesting you do that but it worked in my case. is it like this sound?

When the whine happens, is it a constant tone or does it come and go? 

Comes and goes, or more accurately, more and less prevalent.

On another note, when I was testing things this afternoon, I noticed that my Further put out a loud hiss when any of the three bright switches was engaged.

Bill, tgo

I replaced the Strat set PUs and electronics with another set I got off of Reverb a few years ago.    Everything seems to work fine except for the Q switch.  The middle seems to be giving more than a 6 db boost and in the third position, the guitar emits a loud high pitched squeal.   Any helpful thoughts greatly appreciated.

And still getting a prominent hiss on my Further on all three PUs in the bright setting.

Bill, tgo

Can you post a picture of the STR electronics? Need to see the values of the capacitors on the filter board in particular, and also the axial cap on the Q-switch itself. If possible, can you show both sets? 

On the Further hiss, is this something that was absent earlier and just recently came up? Or is it something you just noticed - meaning did you just recently use the bright switches and notice it, but previously didn't use the bright switches?

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