Does it light up when you press it or just stay black?
I noticed that if you press the LOCK button and then press the screen it says whatever you programmed in for the locked screen message. Then if you let the screen timeout to black, it does not light back up when you press the screen.
It seems like it is dead. Maybe you are pressing the lock button when it is in your pocket or something?
This is different from when you have a password set and let it auto lock as then the screen will light up upon pressing it in.
But when it is in this black screen mode if you press the LOCK button on the top left or press the RED HANGUP button, then it lights up the screen and either asks for the password or says the "Screen is locked. Press the Lock button to unlock."
Then you have to enter the password.
I am running .106 hybrid OS I think I saw this on .103 also. I am not sure I ever used the lock button prior to that so i do not know if .75 acted this way or not.
