I transported my D180 *very* carefully in a kind of crappy rack case that was snug but had no screws... plugged it in today and couldnt really get any volume out of it. I noticed one tube running super hot and turned it off. I opened up the guts to check if a screen grid resistor blew or if anything was obviously wrong down there... they all looked good. I removed the tube in question and swapped its opposite matching tube into the problem slot, and put a different (probably unmatched) 6L6 that I had on hand in the "good" slot. No volume at all! All of the power tubes were firing up fine, when I took if off Standby, they all got a typical blue glow, etc. After a second thorough general inspection of obvious things I tried it again and managed to get a hair of volume. The tube in the bad slot started glowing and I turned it off. Final test- swapped speaker cable (since the cable I was using was brand new and I'd never tried it before), same issues and looked like additional tubes were getting hot (beam forming plate looking orange in a scary way) as the tiniest bit of sound squeaked out. I'm done tinkering, time to ask you guys. Any thoughts?