I can’t change the behavior of SF ..
.. but SF use modified yt-dlp for dl from YT
And with yt-dlp, I can’t see any restrictions
example: single file with two audios (one line)
yt-dlp --audio-multistreams -f bv+ba[ext=m4a][language=en]+ba[ext=m4a][language=no] https://www.youtube.com/watch?v=z3hMX65Khtg
and this works also with Playlists - example:
yt-dlp --audio-multistreams -f bv+ba[ext=m4a][language=en]+ba[ext=m4a][language=no] --playlist-items 1,2 https://www.youtube.com/playlist?list=PLRcHmntfmJ8BNpfON92grhkv6WxuqF5vD