fifty/fifty 1 tube burning red hot.

[masher]

My 50/50 has some issues but had been working fine up until yesterday.
I turned it on flipped the standby and a minute later smelled a burning smell coming from the rack. I figured it was just dust burning off the tubes but it got worse and worse. I flipped the rack around and noticed 1 tube was glowing red while the others were not. I turned it off took off the cover and noticed the mesa stamp on the tube itself looked browned while the other tubes stamps are white.
I swapped the tubes around w same result, and then swapped preamp tubes around it's still the one socket that has this issue( if you're looking at it from the rear it's the second tube in from the fan, or right).
When I put my face over the amp you can feel the heat coming off the one tube within seconds, the smell seems to be coming from the tube, but everything is so close by I can't really tell if it's the stamp burning off or something inside.
In standby the tubes all light up, but once I flip the switch the tube in question lights up blue then the metal plates inside start to glow.
When I turn it off you can hear it tinging while it's cooling down . Last I checked it was still letting sound through.
Any ideas?, I was going to take it to a shop today, but figured I'd ask around first.

 

[Old BF Shred]

Sounds like the first tube shorted and took out the screen resistor. Now that socket will damage other tubes you put in there so....don't.
Not an uncommon issue in tube amps and not generally difficult or expensive to fix, assuming no other parts were damaged. But yea, you need to take it in to a tech. (And you will most likely need to replace the tubes that were glowing).
Good luck!

 

[masher]

I guess I'll have to take it in and see. Looks like It'll be a pricey repair if I need to get new tubes. 1 hr min shop time at 95.00 + parts, tubes. I also have a volume pot that has some issues and some static when I first come out of standby for a minute or so.
Oh well I've had it for close to 20 years so what can I say.
To bad on the tubes they're not new but have low hrs.