Broken/Grounding Issue Metal Muff & CoPilot Fuzz - Need help

[tashiattack]

Saw a listing for a pay what you can "broken" copilot fuzz and metal muff. Offered the seller 15$ (CAN) for both. He said he wasn’t sure why they stopped working, that it was all of a sudden, and that they were both missing the back plate. I thought no big deal, I'll try to fix it, and at worst I'll lose $15.

Came home, put the MM into my pedal board chain and….it was working fine! I was scratching my head. Why would this dude say its not working?!

Then I decided to plug the MM directly without other pedals and.... it wasn’t working. Ah okay...

Exact same issue with the copilot fuzz. It works in a chain with other pedals but not directly plugged in (and also the LED on the boost side of the fuzz is not working at all).

So I’m guessing the original owner used the wrong power supply and fried something on both, so both pedals now have a grounding issue, as they work fine when plugged with other pedals but not alone.

Can anyone help explain how I can fix this issue? This is an easy fix right? I can't use a soldering iron for shit but I can ask a friend. I posted the guts for both below. Also what type of enclosure is used for the metal muff/xo series, as I think I'm just going to order a new enclosure of the same size and use its back plate.

I think this was a pretty good deal

Metal Muff:


CoPilot Fuzz:

[crochambeau]

I'd guess you've a disconnect between inlet power supply ground and the circuit, that is remedied once the ground plane can be completed through a companion pedal.

Confirmation of this theory would require a multimeter on your part.