My keyboard backlight isn't working... whenever I try to turn it up it gives a circle with a line through it. I have read that there is an ambient light sensor that turns off the keyboard backlight when it is too bright, however that has NEVER happened before and I have used it in direct sunlight and the backlight still obviously works. It's not even bright right now but it won't work. This is very frustrating, there should be no sensor that turns it off it should be the brightness I tell it to be. Anyone know what's up or how to disable the freaking sensor?