Can moving wire location at circuit breaker reduce hum?

The current culprit is a Marsh amp.  Lights but no dimmer switch.  The house was build in 2001 but I upgraded the receptacle with one of the audiophile-approved  Randy’s about a year back.

I’ve always had a problem with this room and initially thought all my gear was going bad until one day, on a whim, tried a component in another room.

One of my daughter’s friends is an electrician.  I’ll probably have him look into it.

Thanks, all.

Cheers,

Mamoru

OP:  I encourage you to replace all upstream outlets if they use backstabbed connections. Again, not suggesting you spend a lot, $4/$5 per outlet for new, commercial grade/tamper resistant.

I installed a cooktop about 3 years ago and it became nightmare of noise in my REL subs. At first, I had no idea what was making my subs hum. It wasn't a ground loop. I sent them to Pyramid Audio and they found no problem. I have 4 dedicated lines & a Furman Ref IT15 and they did nothing to silent the humming. After much research, I determined it was a DC issue caused by the cooktop. I purchased 2 Emotiva DC blockers & no noise

@jb1 That's interesting.  Was the cooktop 120V or 240V?

One of my daughter’s friends is an electrician.  I’ll probably have him look into it.

Well done on the plan.