Original language first
The title page says which language a title was made in, and the languages page filters the catalogue by it, so you know before pressing anything. The original title sits beside the English one on the card.
Vietnamese films
A Vietnamese film on a global service carries Vietnamese audio with English subtitles, and sometimes an English dub; on a Vietnamese service it carries Vietnamese subtitles as well. The service's audio and subtitle menus list what is there; turn subtitles on in the player and it remembers.
Hollywood titles abroad
A Hollywood film on a service outside the United States usually carries the local dub and subtitles beside the English track. The audio menu names the tracks by language, and the title page here tells you the original one.
Dual audio
A phrase from the days of downloaded files with two tracks inside. On a service every track the title has is in the menu, so the dual-audio version is the title with the menu open. Switch during playback; the subtitles follow.
