Apple TV display zoomed in, icons oversized

I've had an Apple TV 2 for 180 days; it's always worked fine. I just went to use it again, however, and the display was as if it was zoomed in or in some kind of safe mode. The menu icons were oversized and the ones on the side ran off the screen.

It's connected to the same Samsung 1080p TV it's always been connected to—and the TV works fine when I watch regular over-the-air programing. I adjusted no settings on either the TV or Apple TV before I enountered this probem. The TV 's display says 1920x180 @60Hz The Apple TV's video was set to auto. When I changed that setting to 720p, everything fit on the screen. But I have a 1080p TV, so I shouldn't have to do that. I reset the Apple TV holding the Menu and Down buttons on the remote for six seconds. I also unplugged the device. And I restored it. Nothing helped.

How can I fix this problem?

Thanks!