Every once in awhile, while watching a movie on Netflix, the audio and video would go out of sync. Watching a foreign language film with closed captioning was sometimes funny as the words I read had nothing to do with what I saw happening.

Edit: I also bookmarked your OP to remind me to get the app.

It's a free app and made Netflix much more enjoyable.

BTW, sometimes the captioning doesn't work at the start. I turn it off for a minute or two if it freezes. I got used to captioning watching anything at my cousin's house. She is deaf so the captioning is always on. Now, I wouldn't watch without captioning, especially if there is any fast paced dialog.