Thanks, all, for comments.
Basically you reinforced what I believed/suspected.
One comment: You'd be surprised at what the interior
of the MACs look like. Amazing attention to grounding
and shielding. We'll see if Pin 1 raises its ugly head,
when I get the amp back up.
I'm ready with ferrites...and have decided to turn the speaker
leads into twisted pairs...good advice, from whomever it was who
Will report results, as this story unfolds, in the event that
there's something to be learned.
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