streaming issues when connected to receiver

ok here's one for you ... I have a 3rd gen Apple tv (I think I do, its the 720p one that came out before the 1080p version) i have sony S-air surround sound. the receiver for the sound sound is connected to my tv Via HDMI... I have the apple TV, blu ray player, and PStv connected to the receiver via HDMI.... I have had no problem really with the streaming of the apple tv until I connect it to the Receiver . I have the Apple TV connected through ethernet, and everything is lighting fast at first.. .. if I'm watching youtube it will be good for a while, then the sound cuts out, and a few seconds it stops. I then have to wait for it to catch up... It didn't do this when it wasn't connected to the receiver.. is there a setting somewhere I am forgetting to set?? you would think it wouldn't do this connected to the ethernet... sorry for the confusing question, any help is appreciated.