Hi, I just joined to post this to see if it's common and maybe reason for battery drain. I noticed sometime when coming out of lock screen that my camera ap was open. But just now I tried to see if siri worked from lock screen. Course she doesn't. But what I heard is the camera clicking focusing and unfocusing. It's very Very faint but mine is definelty doin it. It's even doing it on this screen but Siri kicks in sometimes so drowns it out. Great forum.