hybrid creates an unplayable file.

[Selur]

No, Hybrid is not reencoding the content.
The problem seems to be that mkvmerge thinks the content is H.264:

'K:\temp\2024-07-12@22_11_17_1610_04.vp9': Using the demultiplexer for the format 'AVC/H.264'.
'K:\temp\iId_10_aid_0_lang_en_2024-07-12@22_11_17_1610_02.aac': Using the demultiplexer for the format 'QuickTime/MP4'.
'K:\temp\2024-07-12@22_11_17_1610_04.vp9' track 0: Using the output module for the format 'AVC/H.264 (unframed)'.
'K:\temp\iId_10_aid_0_lang_en_2024-07-12@22_11_17_1610_02.aac' track 0: Using the output module for the format 'AAC'.
The file 'D:\clips\!_bestvideoforum\5_2024.07.07\conv\2024-07-12@22_11_17_1610__05.mkv' has been opened for writing.

Not sure why Hybrid uses mplayer for extraction, this is probably the cause of the problem.
=> I'll look at it. As a workaround, enabling "Config->Input->Extraction->Stream extraction with ffmpeg" should work.

Cu Selur