i got this error and i don t know what to do. could you help me?
Ultimately, it will probably require that you provide the file triggering this assert failure (controlled shutdown of an application before evil stuff can happen) as a sample, but for now it would help if you install the latest MinGW build of Avidemux (Avidemux cross-compiled for Windows on Linux) from here (https://avidemux.org/nightly/win64/), start Avidemux, try to open this Matroska file so that it crashes, then attach %appdata%\admlog.txt to your reply.
The reason I ask you to use a "win64" cross-compiled build is that native builds compiled with Microsoft Visual Studio (VS2019) on Windows write log file buffered ( = with a delay), so I am not sure that such a build manages to flush its last words to disk.