I have an MKV file with multiple subtitles. I would like to mark one set of those subtitles as default, so that it is turned on by default when the video starts playing. NOTE: I do not want to "burn" this subtitles set into the video (I want to be able to turn these subtitles off at any point in time if I so choose).
Is there an MKV editing tool that would allow me to do this?