I’ve got a problem with my streamliner 600, after a while, like half an hour or so, using it it goes silent, like the power been switched off, but all the lights are staying on, after a minute or so it comes back alive, like nothing happened. I think it’s the pre amp cause I plugged a lead into the AUX IN and it made a noise when I touched the tip of the jack plug, so the power amp seems to be working. Could it be just the valves? Any idea? I couldn’t find a proper wiring diagram for it either so my limited knowledge of electronics is even more limited lol