I have the HTC Desire HD and my 4 keys at the bottom of the phone (Home, Menu, Back and Search) do not light up very often. I've had he phone for 1 month now. These keys should always light up as far as I know. I thought it was a sensor thing but even indoors in the dark they do not come on. I've seen them lit up maybe 3 or 4 times since I've had the phone. This phone has never been dropped, banged around or damaged in any way. Any Ideas or suggestions?