I know there is huge desire (hope is a better word) that some weird thing will fix it. But there is a point you know
the power amp has a problem. Because no one has had it happen and MANY people have Mac/B&M combos
its got to be the amp if every speaker in that room will act that way. Did they have an MRI machine that went
haywire above your apartment? Is Tesla in the building? Did Magneto escape or did they ever catch the guy?
Is floor 13 missing on the elevator selection but actually there?
Are you on drugs or worse not on drugs making this up, humming in the background? LOL Is your partner
messing with you. Mine will move a speaker just to mess with me. I'm wondering?
All kidding aside, the amp? Get anything, anywhere and see if it goes away, a stereo amp will work fine.
I've know of at least 6-8 mac amps failing more than 1/2 were vintage valve, 3 or 4 were SS.
I've actually seen more drops or shipping stuff than anything. Glass mainly but the corner drop and tweak
is common because of weight. Freight only for me. If its' 5K or more, strap it to a pallet I don't care if it's
5 lbs. It's safer. All my newer Mac gear was sent by pallet double boxed, labeled as GLASS, Handle with care!
Good luck, NC500oems are pretty amazing, and amazingly inexpensive. 2k or less for 3 channels and a
great backup amp or bi-amp once the old Mac is up and running.They are like TT one is never enough.
I'm not sure you can have to many, maybe.
Regards