The rear info screen on camera sometimes stops coming on when I press the Menu button or any button. No damage, no dropping, battery charged, turned it off and back on, too. It's top info screen does work, but it doesn't show Menu & Tools functions needed. Camera shoots fine, and rear screen even BRIEFLY lights up for 5 secs when a new shot fired! Happens 3 times in 4 years seemingly at random. Help please?