Cant connect the remote to Apple TV

My apple TV is suddenly not working. It will turn on as soon as the cable is put in,but that is basically all I can do. When I push a button the flash on the Apple TV will flicker, but nothing on the "menu" will change. I only have two options, but cant go in on any of them. It will sometimes turn the volume on my iMac, or turn on iTunes. It wont help to change TV either.
I would really like some help to connect the remote and the apple tv.

Sincerely, Vilde
Thanks in Advance