Recently bought a Nintendo switch. Connected it to wifi and it constantly drops connection while playing games. It shows great signal everywhere in my apartment. I had the switch at my brothers house who also has xfinity internet and it had no problems staying connected to his wifi. Whenever i test the connection or device it can never find a problem with anything but something is clearly off somewhere.
For a test, does it still disconnect when using a hardwired ethernet connection directly to the router / gateway device ?
You would have to buy an USB-C to Ethernet adapter to test that. So id say they probably dont have that.
Although it sounds like they are connecting to the Xfinity wifi that you see in a neighbourhood, versus the actualy SSID of their Access Point/wifi enabled Router.
I know if you connect to the xfinity one, there can be issues. Ive seen that problem.
Id say, forget the connection within the Nintendo Switch, refresh the wifi on it (re-scan), look for the name of your wifi and try connecting to that.
Do you seperate channels 2.4 and 5ghz? the switch should work on both, but connect to the 2.4ghz, as i know even though 5ghz is supposed to be faster, the switch seems to have issues with it (I have a switch and on 5ghz i had all kinds of issues), and on the 2.4ghz the switch works flawlessly. Try that, and post back.