Sorry for a VERY general question. Fired up the hifi last night and got a loud, constant buzz through one speaker. Volume control doesn't alter the level. I'm pretty hopeless technically but done some checks and narrowed it down to the preamp channel, not a cable or amps.
Before I take the lid off, could anyone take a guess whether this could simply be a blown valve which I would be able to swap out myself ?
Anything other than that and I'm stuck.