Yes, that’s a start! That’s encouraging. It seems like something is shorting…like the back of a pot against a lead poking through the paper. Are you sure no leads are poking through the insulation paper? Make sure you trim all of the leads that are under the pots to ensure they can’t poke through….especially on the relay and microcontroller.
Use some different insulation paper if you need to. I think you are close to getting this to work.
The dark tone is probably from the HIGH side signal path not working due to the jumper issue…we can fix that once it is working reliably.
Keep me posted.
Good luck.
-Brach