A friend of mine moved, pulled this thing out of his basement and gave it to me without any user manual. It worked well for a while, but I wasn't aware of the purpose of the two power buttons. I ended up using the main power button to power down the whole machine (the one that shut off the fan the same time as the lamp). I figured it was safe to assume the lamp overheated. Anyway I bought a new lamp, put it into the machine, and there is no response at all. Neither power button has any effect and it's like the machine isn't even plugged in (it is though). Any ideas? Could it be a fuse or something?