Universal Beamforming can trouble some older adapters. I would not expect it to affect many clients.
My suggested WiFi settings:
- set 2.4 WLAN to n-only, 20 MHz, ch 1,6,
11 or 1,5,9,13 (non-overlapping, least congested), WPA2-Personal AES*
- set 5.0 WLAN to n/ac-mixed, 80 MHz, ch 149,
153,157,161,165 (non-radar, highest Tx power), WPA2-Personal AES*
Disable Airtime Fairness per band. And Universal Beamforming per band IF it improves a client connection.
The Roku is probably just fine.
Neighboring WiFi can interfere. Use a
WiFi Analyzer to see what is around you.
OE