Hi Guys, I bought a Vox AC4C1 about a year ago and I am really pleased with it. However, I got it out on Sat and it had stopped working completely. No sound coming out at all, it was fine the previous time I had used the amp which was a couple of days prior to this and it had worked fine. I unplugged it and put it away as normal but the next time I got it out there was no sound at all. I should point out that I always allow it ten mins to cool down before moving it as I know that valves (or tubes for our American cousins) can sometimes blow if you move the amp with the valves still warm. I have never moved the Amp straight after turning it off. I have had the back off and looked for obvious faults like a cracked Valve (tube) and I also powered the amp when I had the back off to see if all the valves lit up and all the valves lit up like they should do and I also checked the fuse and that was OK as well. My main question: is it possible for a Valve (Tube) to be faulty and not working but still look as though it should work because it lights up and there are no obvious cracks? Has anyone experienced this fault or can they suggest any thing obvious please? I am hoping it is one of the valves but I don’t want to go buying an another set of valves unless I know for sure this is the fault? Any help or advice much appreciated. Thanks guys.