Hi everyone,

I recently purchased a Marshall SB Mk2, in fairly good condition. When I flip on the standby switch after the amp has warmed up, I heard a faint hiss or noise. This doesn't increase with volume, but is quite audible. This being my first valve amp, Im not sure if this is normal or not. I plan on changing the head to cab lead, as this seems so be a very low quality cable, but I don't know if that is the source of the noise/hiss... :-\

Any help/suggestions?

Thanks!