Rob5246 posted a topic in Spider ValveI brought a Valve HD100 MkII head with matching cab from GAK in England a couple of months ago now. It started off fine when I was just getting used to using the amp. As I brought it to practise with my band, half way through playing almost all guitar input was drowned out by an intense buzzing / static sound. Ever since then it's been slowly getting worse to the point where it's completely unplayable, I just can't use the amp. The second I turn it on, I hear a faint humming starting up (that shoudln't be there with the standby switch off!) then as I hit the standby, it's instantly doing the huge whirring sound again. Sometimes however I can just turn it off and on a few times, and it calms down, and I can just about get away with using the amp... except then the volume pretty much doubles all by itself, and keeps jumping up and down abruptly then the buzzing starts again. If anyone has experienced this before, or knows what to do to fix this, please let me know! I have no experience with valve amps, and I've put off fixing it for way too long! PLEASE HELP!