This has happened to me on my xboxone. My screen will freeze up and exiting out to quit with the large white xbox button does not work as well - frozen. After going to settings and testing the network connection I always get your network is good the problem is on our side (meaning Microsoft - xbox). In my case they are aware and are still working on the issue. My party chat will still work. hopefully this is the same case with your problem unfortunately all I can do is wait for another [u]xbox[/u] update.