I use my Mac Mini as an iTunes serve or my Apple TV. It's pretty much all it does now. About once a month, the display will come on on it's own and it will just be a gray screen and whatever I'm watching on the ATV will eventually stop. This just happened tonight. The last time it happened, everything that I had watched earlier in the day had the last played stats not updated in iTunes. We're talking the whole day even though I was able to play those shows and iTunes appeared to work fine that day. The screen comes on and it's just a blank gray screen. The only thing I can do is hit the power button. Anyone know what this is and what is causing it?