C6300 5ghz wireless network disappears

Folks, the same is happening on my C6300! I notice it on my phone Wi-Fi. It will randomly be connected to "2g", bring up available networks with no "5g" available. Reboot also brings everything back to order. May be coincidence, but before my latest reboot, my PS4 internet speed was 39Mbps download (I have solid net @300Mbps) Reboot brought "5g" back and my PS4 back up to a customary 190Mbps.