Okay, since it does work with x264&co and only fails when ffmpeg based encoders are used, I would need a debug output to be able to reproduce the issue. 
-> okay, I see the issue.
The expected output file isn't properly detected.
-> will look at it after work,.
-> okay, I see the issue.
The expected output file isn't properly detected.
-> will look at it after work,.
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Dev versions are in the 'experimental'-folder of my GoogleDrive, which is linked on the download page.
Dev versions are in the 'experimental'-folder of my GoogleDrive, which is linked on the download page.