Ok, it's not really a problem since i managed to discover how to avoid it, but still I'd like someone to explain to me what the hell happens with my amp:
The thing is that when I turn it on, plug in my guitar and start to play with the amp volume set to 5, after 10-15 minutes the volume drops for about a minute, then come back to normal. Even if I play for 6 hours after that, it doesn't happen again. Last time, I was playing alone, waiting for my bandmates, but i set to volume relatively low (at about 2,5). No volume drop occured. When the whole band started to play and i had to set the volume to 5, then again nothing happen the whole time we practiced...
I don't understand what's happening, I've used tube amps before but I've never had that sort of problem.
Is there anyone that can explain it to me?
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