I am sick of failing amplifiers

[Atmasphere]

Many times. It's the amp. The microphonics as I call it, or hyper sensitivity always stays with the amp. I had to damp the chassis to some degree to shut it down. If you lightly tap the input or driver tube, it's a loud clank out through the speakers. This is with 1 amp only. The other amp does not do this. And I have swapped the tubes. Many times. It's never deviates from the one amp. The manufacturer thinks it's a bad solder joint. I think it's a persistent problem that was always there and was never resolved because the tech that worked on them only altered one amp to be up to current design. It's a clearly different circuit design between the 2 amps.

I've seen coupling capacitors be microphonic.

 

[Kingrex]

I've seen coupling capacitors be microphonic.

That could be it.
Per my post in the SET thread. After repositioning my speakers, My kT88PP Blade amp is so much better than my SET 845, I will be ignoring the 845 for a while. I am shocked how good the Blade is at bass. And everything else. Blade is a transformer coupled, differential design PP with a Mercury rectifier. As well as tube voltage regulation, tube driver and a pair of KT88 power tubes. Mostly Monolith iron. 78 lbs per 40 watt monoblocks.