Wi-Fi & connectivity

[BraddockTVs]

I have several (10+) Roku smart TVs that I purchased in the spring of this year that connect to a residential/corporate school network.  As of March through June, they all connected just fine.

The network requires that we register a MAC address with our network security system before they will connect.  During the spring, the TVs passed through the network security and web filter without a problem.

At some point this summer, a number of changes occurred to the network and the TVs were no longer able to connect to the wifi network (let alone get out to the internet).

Is there a wifi protocol or feature that we should be checking to get these dozen TVs back online?  Or an IP that we need to whitelist?  We have the ability to modify the wifi network and wired network security to get them back online but we're not sure what to change.

We appreciate the help!

[atc98092]

Are the TVs still seeing the network, and won't connect, or are they not seeing the network at all?

For the former, check your WiFi access points and make sure the 2.4GHz radio is using Mode B/G/N. If it's set to G/N only, some Roku devices have a problem with some access points. There should be no such issue on 5GHz. 

If the latter, your access point radios might be using a channel unsupported by Roku devices. For 2.4GHz, the channel must be between 1-11. They will not see or use 12, 13 or 14. For 5GHz, the channel must be 48 or lower, or 149 or higher. The gap between those two ranges are labeled DFS channels, and only the newest Roku players are just now beginning to support those channels.