dunno about auto, probably varies app by app, amperfly which i use has sync whole library or manually select what you need (although, handling of uncached songs is very meh). symfomium works on subsonic according to splash page (which is what navidrome is broadcasting), so that’s kinda irrelevant, it will work with it. This is exactly the reason i use it, it uses open standard (airsonic/subsonic) many people are implementing/using, while jellyfin just does jelly stuff.

While extremely great for movies/tv, where it’s only game in town, handling of audiobooks, music, photos are done better elsewhere, i think. Although it does them well, just other programs do it nicer in some aspects.