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One channel buzz, other channel normal

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I finished the amp yesterday and the right channel sounds great. The left channel has a buzz, sometimes when I turn it on the music out of the left will sound fine for about 2seconds then the buzz "turns on" and overwhelms it. If I turn it on again the buzz happens right off the bat. I have gone through all the checks from TY's photo guide and everything seems normal and matches the other channel. I've swapped out all the tubes and it still does it. I've disconnected the inputs from the board, still no luck. Could a bad FRED cause this type of problem?
 
Yes its the SSE. The problem after much troubleshooting was the input tube socket.

The amp sounds awesome. But now I have new problem, I have some very cheap chinese 6l6GCs and the plates are starting to glow, its not noticeable when the lights are on, and barely noticeable with the lights off. I took a picture of them, which really enhanced the glow, id say its about 1% of what the photo really shows.

Can I fuse the output transformers in case these things blow? If so, what is the best way of doing that and what fuse size should I use?

An externally hosted image should be here but it was not working when we last tested it.
 
That is fairly typical for SSEs with higher plate voltages. What is your B+ voltage? Because of the fairly small currents used in a typical tube amp, trying to fuse the OPTs introduces a fair amount of unwanted series resistance. Even then, the tube may protect the fuse. In the case of the SSE, if a tube shorts it will toast the cathode resistor and eventually blow the fuse on the amp (assuming its fused properly). It might also take out the cathode bypass cap. Both are fairly inexpensive parts in the unlikely case of tube failure. In the meantime, I'd look for other tubes or investigate lowering your B+ by adjusting C1.
 
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