There is one main SSID and another for guest. That's it.

@alawy103 Strange. Some kind of incompatibility with your router?

@alawy103 What about trying 2.4GHz (switch off 5GHz)? What router have you got? I don't see how it's a hardware issue if you've swapped around main Deco. This issue is similar to the problem that...

@TonyReilly I upgraded last week (I got some X20s so the M5s aren't as critical) and glad to see they are working beautifully.

@McFly I upgraded last week (I got some X20s so the M5s aren't as critical) and glad to see they are working beautifully.

@Mwess1113 Try switching one of the other Deco's to be the main (in the app and physically) and see what happens. BTW, plugging the switch into the modem will not work - the switch can only be...