Subtitles from DVD rips don't mirror to Apple TV and Chromecast


I’m a new Infuse user and I use it on my iPhone and so far I’m pretty happy. The only issue I’ve come across is being able to see the subtitles on DVDrips getting mirrored from my iPhone to the TV (via either Apple TV or Chromecast). They show up fine on my phone but they simply disappear when I’m streaming the video. Any thoughts on what could be wrong? Is it a bug? Am I doing something I shouldn’t?