I just recently purchased the BE65 Pro, Tri-band whole home system and it hasn't worked right since I installed it. I've spent hours on the phone and scouring websites, and this forum is where I place what little hope I have left. I paid a significant amount of money for this system and am disappointed with how tech support has handled the issue and how frustrating this ordeal has been. 

The issue me, my wife and roommate continue to have is that we aren't able to load certain applications and websites on our devices. The internet is really fast since setting it up and we have no issues streaming 4k movies from netflix, amazon and youtube, to browsing the web. The coverage is great with the whole home getting great speed tests. It only has an issue with loading these three Meta programs, Facebook, Instagram and WhatsApp. The apps just wont load properly when connected to the wifi. When we disconnect from wifi and go to cellular data, the problem goes away. The issue is with apple and android phones, tablets, laptops and pc. 

I have checked with my ISP and Arris to resolve this issue. We went through several troubleshooting procedures and both came to the conclusion that the issue had to do with the router. I have changed the primary and secondary DNS, the subnet mask key, turned on IPV6, updated all devices and applications, and did the multiple necessary sacrificial on and off attempts. All of these have led to the same issue. The applications work for a few minutes and then go back to not working. SMH

Along with purchasing the router, I got a new modem. An Arris Surfboard S33. 

If anyone can help, it would be greatly appreciated.

P.S. My roommate said that he hooked up his old TP-Link Archer A7 to the system and created a 5GHz media bridge to his pc and the issue went away...... why would that be?