[CONFIRMED] 1st and 2nd subtitles won't display together

[adicoto]

So, haven't used the 2 subtitles option lately and decided to test it on a new file. It's an MKV file with multiple subtitles. Video decoded by CoreAVC, audio by AC3Filter, splitter it's as usual, Gabest. No problem in detecting subtitles, but when secondary subtitle it's activated, the primary goes away and seems that it doesn't get back.
And also, when changin on the fly the subtitle, you need some 15 seconds before the new one it's displayed.