I've run a vnc server on the device, and connected with my laptop. Seems like if I change the "brightness" of the n950, it will bring back the backlight. So in other words: the backlight of the screen will set to 0 everytime I've put the phone on standby. Edit: somehow, now that I changed the screen brightness manually 1 time, it just magically works! Maybe it has to do something with N9 QTweak? I disabled the automatic brightness before. Could this be related?