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[vinny jr]

I noticed on these 4 keys they seem to have a ind of their own? Can not figure any normal pattern when they light up and don't light up. Has anyone else noticed this or am I missing something. My Sensation's keys light up whenever I touch the screen, My Amaze doesn't and seems to light up whenever.
Vinny

 

[sebastiau]

I think the light sensors on the front determine if the keys light up. I was in a car around 5pm and the sun was shining through the windows. the keys didn't light up then. But i was in a dark restaurant and the keys lit up.