What model of Apple TV, 1, 2, 3 ? What type of TV do you have and do you have any strange connections like converting HDMI to DMI ?
I had the same issue on my Integra 8.9. I have an apple tv 3 and couldn't get it to work. I also have a Integra 5.8 and the Apple TV works fine.
Some TV's/Receivers just don't play nice with the Apple TV is my guess or something funky with the firmware. I also tried multiple Apple TV's.
I ended up replacing my TV with a HDTV and I believe this made it play nice. I spent a lot of time researching this, but ultimately could not get it to work with the old TV (old rear projection)