Hello all, I wonder if anyone had experience with this particular amp? For reference it is the larger Tweed effect head of 100w, incorporating 3 x 12ax7 preamp valves and 8 EL84s in the power section (in four pairs). Very nice in-between Fender/Marshall sound wise, quiet, nice reverb, plenty of power. Had mine at least ten years but it had been rested a long time, and has recently developed a fault. It will play nicely for anywhere between 10 minutes up to and hour, but then intermittently makes a loud 'pop", then some crackling, further pops then cuts out. So far some preliminary checks: Sprayed switch contacts on front panels and jacks (very brown and gunky switches) Bridged the FX loop at the rear with a patch cable Observed the valves/tubes during said "popping", no flickers, no indication of obvious failures. Read up on the fiendishly difficult to repair circuit board! Any advice or troubleshooting points much appreciated! Thanks!