Error and crash when trying to save file

[King Mustard]

I have an AVI video file that I want to rotate 90°.

I open the video file in Avidemux 2.8.1, use Video Output as either 'HEVC (x265)' or 'Mpeg4 AVC (x264)' (same crash with both) and use the 'Rotate' Filter.

Output is set to 'MKV Muxer'.

When I go to File, Save and click OK, I get:

Assert failed :0 at line 409, file F:\jenkins\workspace\VS2019_no_import\avidemux_core\ADM_coreMuxer\src\ADM_coreMuxerFfmpeg.cpp

The application has encountered a fatal problem
The current editing has been saved and will be reloaded at next start

Ayn ideas?

[eumagga0x2a]

This assert failure means that a PCM audio track has an unsupported bit depth (only 16 and 24 bits are supported).