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Did you try inserting an inverting buffer in front? Something like the SHO. I think it could help by making the input and output out of phase to stop constructive interference.

From what I've experimented with; having just a random buffer in front doesnt fix the squealing, but having a pedal (or buffer) that inverts the signal helps negate the oscillations. So this is what I think happens:
- Plumes has 4 stages and the output signal has the same phase as the input signal. So, the signal from the output somehow gets picked up at the input and amplified again ie. constructive interference happens. By sticking the inverting buffer in front input and output signals become 180° out of phase which means that destructive interference happens which should mean that oscillations are cancelling themselves.
Just to clarify, I'm not an expert and this may be waaay off. This is just me trying to explain stuff to myself using sparse knowledge of physics and electronics. I've used this with other pedals that have the in and out signals "in phase" and it helped negate the squealing.
Sorry for the long read and good luck!

I've had Scarlett 2i2 2nd gen for couple of years, never had a problem with latency. I've even used it for small gigs (acoustic guitar and vocals with some effects in ableton then straight out to active speakers) and it worked out just fine. I think they sorted out the latency and clipping problems of the 1st gen.
That's just my 2 cents, I hope you will find the one that suits your needs.

Hi again,
yesterday I tried soldering the jacks and grounding pot casings, that seems to have little to no effect.
I've also fiddled around with filter of the capacitance multiplier, that really didn't matter either, it was already clearing 99% of the supply ripple.

What I've found helpful is having low pass filter in front, but the pedal's response felt weird... So I've kept just the 1nF cap from input to ground as used in MXR Dist+ (supposedly to block RF noise, but I'm no expert). That worked great, no extra high end seems to be lost and I think this is the solution I was searching for. Maybe changing the cap value has some effect on the response, but this seems like a bullseye.

So I hope this thread could help someone that gets stuck with this kind of problem (there's a lot of similar cases on forums). Thanks WormBoy for all your help!

I've been testing without a box (just a simple alligator clip testing rig), so I don't expect it to be completely noiseless, but I didn't expect that high pitched noise either lol

Thanks for your reply, I will try to rearrange the wiring to see if it helps. As i said, it goes quiet with an SHO in front, but stays noisy with ic buffers in front... maybe a mosfet buffer would help? I'm really just guessing.
But, what did help is a capacitance multiplier before the inverting stage on the board, now the squealing noise appears only when every pot is almost maxed out. I might try and adjust the corner frequency later today to see if i can completely eliminate the noise.

EDIT: I forgot to say, I've tried 2 different layouts for Plumes, both turned out to be noisy

Firstly, hello everyone and thank you for sharing your vast knowledge here. I was thinking about posting sometimes and I was both overwhelmed and inspired by the community so I was just lurking in the end... I have couple years of experience in electronics and programming but nothing too crazy. I'm excited to learn from everyone around here.

So, I was trying to build EQD Plumes (2 times) and Keeley Oxblood from tagboardfx, they both use 1044 voltage inverter and I can't seem to make them quiet. There's always squealing with gain maxed (I like testing/having the whole range).

Already tried:
- checking for shorts and misplaced components
- adding more filtering on positive and negative lines (larger electros and 100nf mlcc)
- using 7660s and 1054 (with pins unlinked)
- using battery power and tl071 buffers
only thing that seemed to help was putting another pedal in front (I've tried with SHO, TC Spark and Digitech Drop). That seems to eliminate the high pitched squeal and leave only the "usual high gain motorboating/sizzle".

If anyone has any ideas about reducing the high pitch squealing without putting another pedal in front or some explanations why this seems to help the situation, I'm all ears. Thanks for all your shared knowledge and for this amazing community.