Got a solution. Seems that the UPD multicast traffic was too high (over 100 packets per sec) so it was being dropped. Apple devices are very chatty, so having so many devices would make so much chatter that it was affecting multicast/ bonjour. I did something interesting, I made an outbound rule for the SSID to deny all UPD "224.0.0.251/32". That stopped the MDNS traffic to the upstream, but keeps it working within the same AP, so depending on your AP density this will work great (does for us). All cabled printers are accessible now via AirPrint rock solid and we filtered so much trash that the Network is now using less power all together as it doesn't have to broadcast all that.   ... View more

Are the AppleTV's on the same subnet as the device connecting to it?  If not have you enabled bonjour forwarding? It's located under Wireless>Access control     I have AppleTV's that are on a Misc subnet that are accessed via devices on two different subnets and they work without any issues.  ... View more