aTV media player not playing PGS Subtitles (Default) correctly on MKV files

I’m trying to play MKV files with subtitles embedded as an option, but not necessarily don’t want them to show up all the time.  I set certain subtitles as default (Forced) using MKVMerger and they play perfectly fine with VLC player, however, using aTV media player the first subtitle included in any MKV file plays automatically when subtitles is turned on.  When subtitles it turned off none of the subtitles, including forced, will not show up.  Is there any way only Forced or default Subtitles play on MKV files, or is this a known bug in media player?  Any feedback/support will be greatly appreciated.  Thanks in advance.   

You can manually choose the subtitle track that is displayed through the Playback Menu.