my buttons stopped lighting in portrait mode for a few hours then started working again. I would try manufacturer's warranty if possible. Good luck.
update... My screen display went out completely! Went to verizon hoping to get Htc warranty but she said because of scratches on the case i'd have to use insurance. I could still receive calls becauseI knew where to swipe to answer. When I called Asurion they issued manufacturer warranty. Btw in direct sunlight I could barely see screen. But capacitive buttons where ok.