Hi All, I hope some of you android experts can help me. I'm in the UK and I got 4.2 for my Nexus 7 over the air this morning. I setup a 2nd user for my wife on my machine. For the most part it works ok but we're getting a let of "lock outs" and blank screens. ie Very randomly the screen will go blank and when I press the on button I'm at the lock screen. I move the lock to the unlock position and the screen loads for about 1/2 a second then I get taken back to the lock screen. I repeat this 5-10 times and then eventually it lets us back in. It then works for a while and then it goes blank again and we have to repeat the above process. Anyone else had this issue? Any advice/tips? Many thanks in advance.