I have a customer who had an R710 that his kid's playstation 4 was connected to with no dramas. Last week I removed the R710 and replaced it with 2 x R600's with the unleashed firmware. I recreated the wireless profile with the same SSID and password and all 14 of his devices (on both frequencies) reconnected without a hitch except for his PS4. I tried all manner of ways of reconnecting it from "easy setup" (on the PS4) right through to entering every setting manually to no avail.
Finally I created a new network on the unleashed master with a different SSID and the PS4 connected straight away and has been performing very well ever since. My theory is that the wireless profile stored on the PS4 for the old R710 had a slight mismatch in a setting somewhere which didn't let it connect to the new AP. I wasn't able to factory reset the PS4 as the guy didn't want to lose anything so can't be 100% sure but just wondering if anyone has seen anything similar before? Ideally I would like to remove the second SSID but suspect this won't be possible without factory setting the PS4.
Do you recall the settings used on the R710 as far as encryption goes? One thing that comes to mind is that Unleashed only supports WPA2 while Standalone still allows you to create a mixed WPA+WPA2 network. Perhaps the PS4 remembered the network encryption type from before and could not cope with the change.
I'm not a PS4 guy, but I'm 99% sure this won't work in "newer" PS4 firmwares. It used to be that PS4 only remembers one wifi network, so if you switched to another, it'd forget the first.
But a while back they did update the firmware and now it remembers multiple networks, BUT does not provide a UI to forget previously remembered networks, apart from resetting the whole console to default settings.