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Oh so happy to report ....that after 100's of builds I still manage to fuck up. I had 150 ohm in R7 instead of 100k
The pedal worked but not as intended. I also found a broken lead for c32 replaced that and we're in business. It doesn't sound quite as beefy and chunky as on the vids I've seen.
  I'm wondering since I had 150 ohms in r7 and got a light overdrive put in the called for 100k and got some smooth distortion so I'm thinking what if I upped it to say 110k or even 120K to coax out all the chunky goodness this circuit has to offer.
 
 Hey Madbean thanks once again for another fantastic layout. Hope you got yours up and running. Got my 2n1306's from Small Bear.

Do you have a schematic? Sounds like it may need some biasing. Do you have a schem?

It's the earlier PCB of the earlier production of the haunting mids. From what I gather, JHS changed the circuit and thus did PPCB.

Just a note
Cybercow over on PPCB had a x1000 PCB at one point. Also, see the proposition PCB. Maybe will scrath an itch.

thanks jwin615, I was trying to do the same as you drew but it wasn't working until I put it in a different spot.
(apparently the signal path branches out right there and I kept jumping in at a point that was ineffective.)

*I edited the post because I figured out I was misreading the layout and got it working.

but I'm still wondering if there's a better way to address this unwanted signal boost?

You have feedback loops feeding other opamps so I wouldn't want to mess with the opamps.
You could attenuated the input, but for noise, you're better off attenuating the output.

Getting the pads correct at the output is critical. Hopefully my layout is right. It was pretty late and been a long week so wasn't working with a full tank.

https://photos.app.goo.gl/4eqE4fGoJaNcDYuy8
How to do upload images on mobile? I don't get it. I swear I did it once. Anyway.
I *think this will work, to add an output volume control.
Also, I *think* you will need to make the link in red but someone check my work.
I would experiment with pot value and taper between 5k and 25k.
I don't see an easy way to alter the volume otherwise unless you just want to tack a voltage divider on the end, which we're doing here. just variable.

Got my 96 rolls of toilet paper yesterday. Ain't doing that again.

Swapped out Q1 anyway and it wasn't that. Did C3 in the process too and it wasn't that either.
This one is about to go into the bin of unwanted PCB's. Unfortunately I had already drillesd the Pot holes in the enclosure before I soldered them to the daughter board so that I could make should they were lined up ok.  I'm sure I can find another 3 knob 1590A build to use the enclosure
Should have been a simple build ... I built one of the BYOC 1590A mini Muffs with 2N5088's a couple of years ago and it fired right up.
I was doing this one to see if I wanted to mod my actual Big Muff to the Creamy Dreamer and I had the Rabbit Hole board laying around ... seen lots of conflicting info on it online but I don't care for some of the other mods out there.   

Reinspect your connections from the pot board. Particularly the ones for the sustain pot. Couple of strands here and there that may be bridging. May need to clean the flux to get a good clean look. If a lug of Sus is bridges elsewhere, that would explain your wonky voltages.

There's schematics of some base modules on the mts forum. You can use those as starting point

Lovely as always!

Don't you need a matched PNP NPN pair for(optimal) push pull? May look at transistor arrays if that's the case.
I assumed this was for a pedal so didn't take voltage into account...

I'll add, check out the Alfa offerings

Triple check for solder bridges around Q1. A lot of your disc caps look like the insulation is going through the pad and a lot of joints didn't flow through the via. May be worth reflowing that first gain stage area if you haven't. The 0v reading could be due to your meter. Assuming it's capable of reading ~40mV, make sure it is ranged for mV.

https://www.madbeanpedals.com/projects/_folders/1590A/pdf/RabbitHole2020.pdf

Voltages in there

Make sure you didn't mix up 100k and 100R resistors in the first stage?
I'm assuming you have an audio probe setup. Are you sure you're losing signal before Q1? I like the break up circuits for initial probing. So, I would probe the collector of each transistor.

Do your transistor voltages look similar to those in the build doc?

Could use mmbt22222

Passive guitar outputs vary but typically quote din the 100-140mVrms range. Actives can get even further up there. Of course, you have to take the next devices input z into account...
There's no standard like consumer and balanced line levels. Instrument level is generally considered 0.1-1.7V
Around 0dBu is probably a good middle ground.