jellysub VS dropcaster

To summarise what we've gotten to so far: - Jellyfin web can do this using Instant Mix feature, but instant mix is at present pretty basic (see discussion here: https://www.reddit.com/r/jellyfin/comments/o0eic8/what_is_instant_mix_actually_based_on_also_is/). It won't work very well at the level of "Artist" but starting from a specific track or album produces a pretty good mix for some music in my library. Instant mixes can be saved as playlists. - Some Jellyfin apps can do this: especially symfonium (android) has advanced features for making mixes. The only limitation here seems to be saving playlists back to jellyfin server. And if you don't have an android phone and sonixd has a very limited ability to create a (completely, and imho unhelpfully) random playlist. - There are more convoluted solutions. Jellyfin users can try to use Subsonic clients with jellyfin by installing a server shim, but it seems this isn't being developed anymore and I wasn't able to get it running. It is also possible to use jellyfin as an MPD server, so more generic clients can be used here too.

For the Jellyfin API it might be worth adding https://github.com/nvllsvm/jellysub, it's an API compatibility layer to let Subsonic-compatible apps query Jellyfin.

Subsonic

This is a bit of a roundabout solution, but I've been pretty happy with it. First I convert the books to per-chapter MP3 files with AAXtoMP3, then Dropcaster to create a podcast feed of the chapter MP3 files. I just put that behind a simple password protected static file web server, and I can use any podcast client to listen to my books.

If you don't mind getting using Dropbox instead and having to use a command line, https://github.com/nerab/dropcaster should work to give you an RSS feed