.ass subtitles in MKV files

[SherNan]

Hi there,
First of all, sorry for my english, I'm french.
I have a weird problem with .ass subtitles (3D subs). Here it is...
I used mkvmerge GUI v5.8.0 to put the .ass subtitles in a .mkv movie file.
Everything is ok with VLC on my computer but on my 3D Tv, with PS3 Media server, sometimes I have only the left side sub...
Of course, I quoted "use ASS/SSA subtitle styling" in PS3 Media Server
Do I have to extract the .ass subtitle from the MKV ?