It looks like ffmpeg-4 on Packman for 15.2/15.3 is not built with “–enable-libsmbclient” option:
https://pmbs.links2linux.de/package/view_file/Essentials/A_15.3-ffmpeg-4/ffmpeg-4.spec?expand=1
https://pmbs.links2linux.de/package/view_file/Essentials/A_15.2-ffmpeg-4/ffmpeg-4.spec?expand=1
This will cause applications such as mpv can’t play videos with samba protocol.
Meanwhile, Packman ffmpeg-4 on Tumbleweed has the samba support:
https://pmbs.links2linux.de/package/view_file/Essentials/A_tw-ffmpeg/ffmpeg-4.spec?expand=1 Line 615.