My S4 is always connected to the 5ghz and has never had any problems. My partners iDevices are also connected to it.
The other day when I got home I noticed that I kept getting the error 'Your internet connection is unstable' and couldn't use the 5ghz if I wasn't directly in front of the router. No settings had changed, no updates etc. It will discover and connect to the network but it won't load webpages or anything.
There is no new firmware for my router, I have tried all the different channels, and have even reset the router, and as a temporary fix I've only been using the 2.4ghz network. My iPad still works fine on the 5ghz anywhere in the house, and my partner has had no issues.
Has anyone else had this problem, or does anyone have a solution?
I'm running the stock 4.3 on the phone as I haven't even tried flashing it.