You may have subtitles disabled on your TV. Check the TV’s settings, referencing the manual, if necessary.
Verify you have connected the camera to the TV with a USB cable (HDMI or other cables will not work for subtitled playback), then change the TV’s input to USB mode.
Note: USB mode should work after installing our software on your camera (except select Hero3+ Black software versions, see Compatibility tab).
If your TV does not have a USB input, or only plays photos, the TV is not compatible and you must watch the videos on a computer or other compatible player.