Problem with VobSub subtitles

[Idoru]

Here's a weird problem I encountered while remuxing my DVD's into MKV for my hardware player (which is a Chinese no-name called Ravelion HDR1000, but this is irrelevant since it is a generic RTD1073-based mediatank that generally behaves like any other RTD1073-based mediatank out there, since all their firmwares are developed on the basis of the same SDK from Realtek).

For quite some time I had a problem of my hardware player not supporting VobSub subtitles in MKV container, while the player claims to support them (it saw them and allowed to switch between them, but they were not actually displayed). After a lot of research on the web I stumbled upon MakeMKV, which somehow turned out to be able to produce MKV's with VobSub subtitles that were actually supported by my player.

So far so good, but a problem surfaced once I tried to remux an MKV (generated by MakeMKV) with MKVMergeGUI (I needed to add one more audio track to the movie). After I remuxed my MKV with MKVMergeGUI, my hardware player stopped displaying VobSub subtitles from it (while MPC-HC, for example, displayed them perfectly). Then I tried remuxing several other MakeMKV-generated MKV's with MKVMergeGUI, and the result was always the same.

So here comes the big question: how is VobSub implementation in MakeMKV different from than in mkvtoolnix? And is there a way to remux MKV's generated by MakeMKV without loosing VobSub support by my hardware player? Perhaps I should activate some special option in MKVMergeGUI? Any thoughts?

[skittle]

ask mosu on #matroska at irc.corecodec.org
He is the main developer of mkvtoolnix, and will be able to answer your question. prepare to have a small sample for him.