Just noticed this today. Now and then if my phone is sleep mode and I go to hit the power button I get the button buttons to light up, but the screen itself is black. First time I had it happen I did a batter pull and that got it back up and running. It has happened 3 more times since then and each time I can get around it by plugging in the USB cable to charge it. I suspect that between Light Flow and Superuser are not playing right together. I'm running .246 and rooted with razors edge. I do have Light Flow allowed on Superuser which seems to allow the LEDs to work properly. I think before I allowed it was not working right. I did not see an option on Light flow to run outside of root (Before I rooted I had no problems with Light flow on .232 with it being rooted).