bullseye!!!!
think iv sussed it out
a while ago i changed over 2 connectors by accident.... just changed them back over and sounded much better... so now im gonna change 2 of the pre amp valves to low noise electro harmonix and see if the background noise is reduced...
Also is it 100% safe to install the 10 henry choke (100ma) in place of R71???
My tech said the chokes he has seen in other marshalls are bigger and this choke may not be able to take the high amount of current passed though the anodes or something....
Any help on this much appreciated...