Got this little amp today. Had a couple of XD's before normally spectacular little amp. Everything seems to be working fine but sounds slightly muddy to my ears and normally these amps great clarity. Looks like the 2 x 6V6 originals, printed Fender GT. I can only see one valve glowing and only this valve getting warm? Is this because clean channel uses one valve and gain channel uses the other 6V6? Or does it indicate a problem? Speaker everything looks ok. Looks like its had little use but this amp around 5 years out of production so who knows. I am in Thailand and replacement valves looks like my choice Fender GT, TAD or electro harmonix. What would be the pick of those....for sweet clear sound, not overdrive. Or do the power valves not affect your tone? Anyone know about the valves only one glowing and any ideas on the muddy tone? Sounds slightly distorted even at low volume on the clean channel. Should I be looking at the 12AX7?