First of all are you in vod multi subs? If you are you should install for example VLC and use that as a external player with stb emu. then you will both see all the subs and can also pick the one you need.
Yes, if you for example looking in vod multi subtitles there is subtitles. the reason i asked you to use an external player is that i used encore stb and had the same problem that i could not see or change the subtitles. just a guess that you are having the same problems mate.