I have a shiny new cable modem/router and it's running fine but I have some questions about the signal bands.

I set the router up with both 2.4 and 5 g broadcast. My mobile phone picks up the 5g just fine and according to my signal checking app, I have 5g all over the house.

My wife's computer briefly saw the 5g but doesn't see it now.

Our Wii system doesn't see it. My wife's phone doesn't see it.

Only my phone sees it and one of the Kindle Fires.

Are devices specifically configured for one band or the other or is there anything I may have to do in the router setup to make the 5g more consistent?