It could be your phone
I have had an apple TV for a year and it would go in and out for the longest time. It turned out to be interference from my phone. I was on the phone with apple tech support for 3 hours one night and could get nothing to work. As soon as I hung up the phone the apple tv came right back up. My wireless home phone worked on some frequency that bugged out the airport extreme wifi and apple tv. Before I bought my house and lived in an apartment whenever my phone or neighbors phone rang the apple tv would disconnect. I got a better set of wireless telephones and the problem went away.
I have had an apple TV for a year and it would go in and out for the longest time. It turned out to be interference from my phone. I was on the phone with apple tech support for 3 hours one night and could get nothing to work. As soon as I hung up the phone the apple tv came right back up. My wireless home phone worked on some frequency that bugged out the airport extreme wifi and apple tv. Before I bought my house and lived in an apartment whenever my phone or neighbors phone rang the apple tv would disconnect. I got a better set of wireless telephones and the problem went away.