Can't turn voice over off on a Rented film
rented Spectre and it only played with voice over on, even when I tried to turn it off, other movies were fine and even the Spectre preview didn't have voice over
AppleTV 2
Actually sounds like this feature:
Audio Descriptions: Audio descriptions provide an explanation of important onscreen action and content in movies and TV shows.
Try turning it off.
Turn on audio descriptions. In Settings go to General > Accessibility > Audio Descriptions. Or, use the Accessibility Shortcut.