Riffraff

I think you need to elaborate on "bad smell". Is it a chemical smell like something is cooking like the varnish burning of the windings of your output transformer or just something nasty that shouldn't be like a cat pissed in the head box? I would be a worried if it smelled like something was burning and would have it checked out. Check the bias at the very least to make sure it's not running way to hot. I think that would be a good idea given the fact that you are running it that hard all the time.