...I have a Marshall JCM 2000 TSL 100 head, and a 1960a cabinet. Basically I was just playing and I noticed that the volume level was dropping then suddenly it just turned off and now it won't even turn back on!!? I have had no problems before with it and I've only had it for about three months. Hope someone can help. BTW, I know bugger all about amps so please be gentle! If it makes any difference I've changed the plug...same problem Cheers...