I have the same problem. Running iTunes 11 on Win7 x32. Home sharing works when I first start itunes, then stops. Only way to get it working again is to turn it off/on or restart iTunes.
Issue started w/ iTunes 11 install.
iPhone 5 (iOS 6)
iPad 2 (iOS 6)
2 ATV 3's
Same problem on all devices.
Same issue here - have to manually turn off home sharing on the ATV *and* Itunes which is on a PC, it will work for watching *one* 30min movie (well really its a tv episode but it shows up under "movies"). After that the next one we watch never loads even after trying to restart the ATV.
This is pretty pathetic - I love apple products but I'm not a mindless fool, fix this product... there are many other devices out there I could be using (which also have CrunchyRoll on them) in leu of using ATV and other future generations of it
Have you worked throught the Trouble Shooting article
I also checked for wifi interference in Mountain Lion there is an inbuilt Wifi Checker
If you are on an older OSX then istumbler does the same job. On windows use Net Stumbler
This will let you check for wireless interference and then you can change the wifi channel to one not used.
I use Mountain Lion and Apple TV 3 and I do not see this issue