Unplugged my amp and gently placed it on another table to give the cabinet a clean today. When I connected it back up, although the tubes glowed, there was no sound at all. When doing the voltage checks on the speedball I noticed that the led's weren't lit on the large board.
This had me worried and was scratching my head thinking what could have possibly gone wrong just moving my amp? Left it for a few hours and came back to it later, I had the stock tube 6080 so I put that in, did voltage checks, all passed and the led's all lit.
Can't understand how my NOS 6080 Thompson tube could just fail like that.