It's been a while, but I sent mine to Akai UK. When it left my house it definitely wasn't responding. When it got to them, it was, so I suspect they didn't spend any time on looking at it. The issue has since been sporadic, and has been actually usually been fixed by giving it a gentle shake. On Friday it stopped again, but wouldn't come back, so this morning I took a deep breath and opened it up to look inside and at the very least to try and reseat connectors, but the screen assembly is beneath the PCBs, and I'm not really confident enough to take the thing completely to bits. I tested it before putting the case back on, and amazingly it was working, and is now still working after putting back it back together. I'm beginning to think it's something to do with the case flexing or expanding a little with changing temperatures, but that's frustrating as I'm working towards taking it out live and having visions of having to do that before playing.