The bias voltage on the right KT88 reads zero while the reading on the other KT88 is normal ~0.5 v. The reading is zero, not just a low value.
Other that that, the amp sounds fine although I have my preamp's balance control at about the 12:30 position in favor of the subject amp. No hums or buzzes.
I haven't tried swapping tubes left for right -- I'll try that and report back later.
Any hints or tips sincerely appreciated.