apple tv (3rd gen) lost connection with the new modem

I have a 3rd generation apple tv which was working ok since yesterday. I changed my comcast arris tg862g/ct router to arris surfboard sbg6700-ac. I can connect my new laptop lenovo yoga 3 pro, my phone lumia 930, my chromecast, my old laptop (7 years old toshiba sattellite l500d) with no problem to the modem. My old laptop works with both wifi and ethernet connection. All these 4 devices I get full speed internet (with ethernet I get 85mbps wifi speed vary from device to device).

Only problem I have is the apple tv. Both wifi and ethernet connection cannot connect to internet. In both cases apple tv seems to be connected to the router, gets an IP and DNS address. I can even ping the apple tv from the router. But apple tv cannot get any internet connection, none, zero. I reset/power cycled the modem, did several restarts and resets to apple tv. router firewall setting is at low setting. Is there something I am missing?

Thanks in advance.