Hum issue with new Boss ES-8 based Friedman Tour Pro board

Hey, hoping someone can help. This is frustrating us to no end.

We built a Friedman Tour Pro pedal board around the ES-8. Sounded great then a loud hum/buzz came in. We rewired and figured that the metal screws were causing it. We removed the screws and rewired.

The sound was gone, but came back once we moved the board to a new location. We then noticed the side of the ES-8 was touching the side of the Board. We moved it and covered all metal with electrical tape.

Powered up and the hum was gone. Rehearsed with band and about 30 minutes in noticed that the hum was back.

Any ideas on what is causing this?

Thanks!

I should mention we isolated the hum to the ES-8 it does it with nothing else plugged into the unit. So I think its a grounding issue of some kind we just don't know how to fix it.

They have a Facebook page for the ES-8. Might get an answer from there quicker.

Did you try activating the ground lift on the ES8?