You can choose to turn off eJOY subtitles on videos in two ways:
Turn off eJOY on a video
Click the eJOY eXtension icon => Click the On / Off button (1) on top of the setting board to turn off all video features, including subtitles.
Turn off subtitles
Click the icon eJOY eXtension => Select the Upper subtitles and/or Lower subtitles => Uncheck the box Subtitles (2).