It's the Community feature in the main menu. When you enter the Community section and choose "Friends", it freezes the game and you have to hard reboot your PS3 to get out of it. It happens on my machine as well. I have 150/30 fiber Op connection, so it's wouldn't be a connection issue. Last PSN Internet Connection Test I performed was 65 Down, 5 Up. As far as I'm aware, it only started happening since the two-eight hour maintenance periods.