I have had it replaced to no avail.
I *thought* I'd read someone mentioning the breaker was replaced, but couldn't confirm yesterday when quickly going back through the posts, so I wasn't 100% sure and am entertaining Ralph's (Atmasphere) concern considering the breaker's accumulative set/trip cycles, *if* it was still the original. Also, based on first-hand experiences, have had to replace numerous "new" components after immediate or delayed faulty operation, especially regarding a device unintended for elevated repetitive mechanical cycling.
Regarding the amp working at other locations (which I've always taken into consideration), Ralph posted some scenario possibilities that may allow a deteriorating breaker to continue functioning, and I agree is possible. Lacking any witness confirmation, or actually being there to assure apple-to-apple testing/comparisons, all we can do is speculate. He is quite knowledgeable, as with Al and Jim. We all come from decades of professional backgrounds in various electronics fields and offer legitimate suggestions based on scenarios and probabilities we've encountered over the years. All of us would *prefer* to be there - armed with appropriate test equipment - able to make better determinations. That's what I do for a living. So, lacking factual data, all one can do is suggest trying different things with hopes of resolvement.
Your updated plan is fine if unwilling to wait for Ken to return and 'scope your AC (the best *practical* option to minimize guessing). If the two devices fail to resolve, either keep or sell them, and take my joking recommendation to neatly coil-stack an appropriately rated ext cord and hide it out of sight behind other equipment, rack/furniture, etc., or package it cosmetically. You're planning to power the Cary from the conditioner, so, will *all* of the electronics be accumulated in one location near the 20 amp outlet? ...On a vertical rack, shelves, table-top, etc. - thus able to hide a majority of a coiled flat or stacked (black) ext cord?
If the Brick Wall works, it's not very WAF either, so how would you address that vs. a "shaped" ext cord, if the BW doesn't work. I can't envision a scenario where the cord couldn't be hidden or repackaged cosmetically, even if the amp is remoted across the room. It still requires a cord that has to plugged *somewhere*, and you plan to feed it from the SR conditioner. Describe your equipment layout if otherwise.
Again, if we *knew* exactly what was wrong (if anything) with your AC, if not equipment related, could better diagnose and recommend specific cures.