MKVToolNix 9.9.0 发布了，这主要是一个错误修复版本。特别是 MP4 导入模块已经收到了很多的关注，详情请参阅下文。
部分更新如下：
新特性和增强
GUI: chapter editor: added a character set selection in the preferences for text files. If a character set is selected there, it will be used instead of asking the user when opening text chapter files. Implements #1874.
GUI: multiplexer: added a column "character set" to the "tracks, chapters and tags" list view showing the currently selected character set for that track. Implements #1873.
mkvmerge: added an –engage option "all_i_slices_are_key_frames" for treating all I slices of an h.264/AVC stream as key frames in pathological streams that lack real key frames. Implements #1876.
GUI: running programs after jobs: added a new variable <MTX_INSTALLATION_DIRECTORY> for the directory the MKVToolNix GUI executable is located in.
mkvmerge: DVB subtitle tracks whose CodecPrivate data is only four bytes long will now be fixed up to the proper five bytes by adding the subtitling type byte.
mkvmerge: MP4 reader: "ctts" version 1 atoms are now supported.
更新内容较多，详情点此参阅。