lost sound in right tube mono


While listening,the right monoblock dropped out.One slight pop and is was gone.
fuse is good
tubes all test fine
With the amps powered down I read the correct resistance at the pots(10 ohms)but powered on I read no voltage at the pots.The filaments in the tubes are working(glowing)so the tubes are powered up.
Looking inside no burnt resistors or anything obvious.
Thanks for any replies
hot_rod
Bad Bias pot maybe????
check the fuse?
After I stopped whining and stomping my feet I did locate another fuse that lloks to be wired into one of the transformers (B+ rail?)
About a week ago I had a tube loose its bias,thats a sight to see,the whole plate structure glowing red.It ended up blowing the main power supply fuse,but I never bothered to check the other one(didnt know there was one til now)
I wonder if the fuse was damaged and not completly blown and just decided to let go now.
I will post after I power it up
Don't lunch too many tubes trying to diagnose it. Sounds like a bias supply problem.