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A fuzz face to this is less of a jump and more attempting to flap your arms and fly

Oh, sorry, that's my fault, audio at IC11 pin 2 is right.

Well, I think you're close, but I can't think of what to suggest at the moment apart from methodically checking all your values and solder joints in the two areas. You've tried replacing the chips and while not impossible, passives such as diodes, caps and resistors being faulty is rare. Perhaps a week or two away will give you a fresh set of eyes.

Oh, well if you have a scope, you should be able to check the oscillator is working at IC6 pin 8 and that the PWM output is good at pin 6.

If both are good and the divided clock at IC8 pin 12 & 13 is good, you'll know the issue is in the audio path at least.

https://www.madbeanpedals.com/forum/index.php?topic=33146.msg319109#msg319109

In Gordo's case in this thread it was a bad CMOS chip.

I would suggest audio probing too, are you able to follow the signal path?

Oh, okay, when you talked of a static whistle before I thought you were just talking about around D16.

So, if you probe C27, do you have a muffled representation of your input signal on both sides?

Assuming that is the case, the areas to focus on for bad joints, incorrect values etc. will be everything south of D16 anode, so R45-49, IC12 and IC11, R80-85 plus caps.

Is this your very first project then? While it doesn't involve the set up complication of a delay based effect, on sheer parts count alone, certainly a... brave choice
It may be wise after a couple more stabs at it to set it aside and come back to it once you've got a few more projects under your belt, even the experienced builders know when to take a break.

My second guess would be a faulty 150p cap on C30 position...one pin has 8.99V and the other 0.00. burned???

One pin is the 311 output which is obviously giving 8.99V and one is the ground, so no, that's not faulty.

Audio probing is only really useful if you're tracing your input signal, for example on cathode of D16, when playing, you should get a fuzzy octave up version of your guitar signal.

Did you have input signal on pin 3 of IC11?

I suspect it's probably just a bad solder joint or two somewhere rather than faulty components... just a question of where!

IC5 Pin 8, is that really the voltage you get?

Apart from that, I'm not keen on your IC6 voltages but I don't have the schematic in front of me.

You need to be probing IC11 output (pin 7) but first be sure you definitely still have an input signal to it at pin 3 and make sure sensitivity is full CW while you are testing.

Where are you probing when you get the 'vibrato'?

By vibrato I assume you mean tremolo? As in a repeating on/off signal?

Pitch might have been the wrong word, does playing change the on/off time?

Okay, so you wont get octave or anything from IC13 without a square wave coming from IC11.

But, we've determined without IC12, you do get a square wave... does it change in pitch with playing?

IC11 is an oscillator that tracks the pitch of your guitar, IC12 'mutes' this so that it isn't constantly running (oscillating) and you get single notes.

So if without IC12 you are getting a square wave that tracks your input pitch, then the issue must now be around IC12.

LM311 aren't hugely sensitive and you said it worked before, although I suppose it is possible it died with overheating...

What happens to it if you a) remove IC13 and b) remove IC12?

You must have muffled sound (which is actually a sine wave extracted from your input signal) on Q7 collector first, followed by square wave on IC11 pin 7 (follow the schematic) before you get anything on IC13, so you need to find out why that's disappeared again.

But also, your new IC13 measurements, on the second set, you have no ground on pins 4,6, 7, 8, 10... they should all read 0V. Your first set was closer.

You can try re-flowing the solder joints on it again which may be all that's wrong, but they are a static sensitive part so having fried it is a possibility.

Well, only you can tell if the pedal is working and the octave is present now?

If not, that at least tells us that all the signal conditioning circuitry is working and narrows the issue down to the 4013 & Q4/8.

So if you audio probe pin 2 & 12 of IC13, do you get 1 & 2 octave down?

If yes, we know for some reason Q4 & 8 aren't passing it through to the output, if not, replace the 4013.

I should have mentioned, you need the sensitivity control turned up or else there wont be any signal in those areas.

Also, just to be sure, you do get your input signal at IC1 pin 1, yes?

I got sidetracked at one point with scruffie's modulation mod. I put the Vero together. I connected the mod board and a 9mm pot and drilled the enclosure. Man was it a tight fit. The modulation is really interesting but I wish I could have it on a separate footswitch to turn it on and off but there was no room in the enclosure. Ultimately I removed it because it kinda took away from the original effect and I figured I could always run it with other things.

Hey, you tried it! Well, I'm glad it was interesting at least, I was hoping it might make it sound more violin-y.

I'm guessing you didn't get any demo footage of it?