I have had the apple tv for several months now and never experienced this problem. I have a macbook pro and linksys router. Just upgraded to Leopard and have my firewall set to allow all incoming connections. I can't even get Itunes to recognize the apple tv. I can reboot and it will recognize it for a second but when I go to sync it says it can't and to to open port 3689. I don't see that option with Leopard. What is even stranger is that if I get itunes to recognize the apple tv and then plug in my ethernet cable from my mac to the apple tv..it loses all connection. I always sync with the ethernet because my wifi takes forever even when it updates my recently added movies. Any ideas. I've rebooted my router, appletv and macbook but nothing. Okay...nevermind...it is syncing now for whatever reason.