Unplugging the Apple TV at night when you go to bed and plugging in next time u use it will minimize the inconvenience. Of course you can also do this anytime you get the green screen but it usually only occurs after the TV has been turned off. I've heard simply turning the tv off and on will fix it too but hasn't worked for me. I've also heard people say bad hdmi cable connection. I think thats BS.
Good Luck
Has anyone else reading this forum got a handshake problem with the new Apple tv? In case you are not aware of this, or don't know where to start, have a look at:
http://discussions.apple.com/thread.jspa?threadID=2600405&start=0&tstart=0
There doesn't seem to be a solution yet, but I guess we must hope that the techies at Cupertino are getting on with it. Taking some time, though, it's been a known issue (on the forums) since the ATV2 was released.
If you do know about it, or, even better, have a reliable, inexpensive, and universal solution, please tell us all.

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