@ditusa Hi Mike, The Loki does have a wall wart. I’ll unplug it to see if that helps. I have several components that use wall wart style power supplies. I’ll check them all while I’m at it.
I had thought of the bias issue. I’ve read several discussions, especially pertaining to Odyssey, about adjusting bias to change the sound. The only thing perplexing about the bias drifting is that both amps exhibit the identical behavior at the identical time. Can drift in one effect the other so directly? I understand that bias exists and that it is a “thing”, but that is the extent of my knowledge. It is not anything I would attempt myself. You’ve been very helpful. Thank you so much.