Change default subtitle track in Matroska without remux?

[2twisty]

I've got several MKVs that have multiple subtitle tracks.

Unfortunately for me, someone set the default subtitle track. So, everytime I play one of these MKVs, I need to go select my preferred language instead of the one selected by the default.

I'm looking for a tool that can change the default subtitle track of a Matroska without having to remux the file.

If this were just one or two files, then remuxing would not be a big deal, but I have quite a few and this will take quite some time to fix all of these.

I find it hard to believe that there's not a "quick and dirty" tool that can do this.

I've searched and searched with no luck.

I'm hoping the brain trust here at doom9 will have some ideas.