We have xfinity X1 with two wired tv boxes and one wireless tv box. The wireless tv box freezes and buffers quite often almost unusable. Are there possible WiFi settings to improve the connection somehow, maybe dedicate it to 5.0 or 2.4 channels. anything?
As of this moment, there is not any way to access WiFi settings on the X1 boxes.
However, you can try moving the gateway closer to the boxes as @CCAndrew suggested. You could try putting the gateway somewhere close to the center between the boxes.
I have moved the Xi6 closer to the gateway, actually on the first floor right underneath the gateway on the second floor. Still problematic. I also replaced the Xi6 with a new one. Still problematic. It's connecting to my main TV - a Samsung 65" 4K. Interesting that my Apple TV has no issues streaming over the Wifi. Very disappointing.