The behaviour can be observed when using the Android SDK, iOS SDK, or Web SDK in Safari on macOS/iOS. As part of the "automatic media selection feature" on iOS, the presence of closed captions and subtitles, or their absence, must be known prior to playback.
By default, and unless this is explicit within the Master Playlist, the alternate track button, or "CC" button, will be displayed along with the various other player controls and will be set to the "Unknown CC" option as shown above.
There are two ways of removing this additional selectable subtitle:
- When creating your HLS master playlist: Set the
NONEin the HLS Master Playlist file for all variant streams as described in the HLS specification
- Bitmovin Player Web SDK
v8- If you know that this caption track is not needed, it is possible remove it from the player directly in the app without modifying the manifest. In this case,
player.subtitles.remove(String trackID)API call can be used as soon as the player discovered this track. You can obtain its trackID with
player.subtitles.list(), or by listening to the
Updated about 1 month ago