What is your operating system?
linux mint 20.1 (Ulyssa)
What is your Shotcut version (see Help > About Shotcut)? Is it 32-bit?
Shotcut version 22.12.21
MKV files when exported (only when exported) produce this bug.
(I’m sorry for any mistake, I don’t understand much about English or about the program)
I am sorry, but this is not enough information for a bug report. For example, what is the problem? You show a result video, but people tend to use effects. It is not clear what is undesired. Also, “mkv” is not enough info. Is that the source or the export format?
If I have to guess, mkv is the source and the problem is the that sometimes the video pauses. Not every video is a good enough quality to be edited directly. If that is the case, you probably need to convert the source using Properties > Convert.
Thank you very much this solved the problem.