Hey Marshall Forum!
About a year ago I bought my first ever Marshall amplifier; the Silver Jubilee 100W head (with 4x12 cab).
Since I use it mostly at home, I haven't cranked the volume all that much. But when I do, I notice a loud humming noise.
Today I turned the amp on, without having the guitar cable attached to it, cranked up the Master volume (with 0 gain!) and it hummed like crazy.
What could be the source of the humming?? And more importantly, how can I get rid of this awful humming?
The only cables that were attached were the footswitch, FX in/out and the power cable.
Regarding your 2555X, as it is a 100 watt valve amplifier there will always be a hum when the amplifier is turned up, but if you feel it is excessive it may be down to a faulty power valve. We would recommend that you contact the dealer it was purchased through so it can be checked over for you.
Thanks for the info...