Hi,
I just have found this post: balenaSound no services on raspberry pi 3b - #5 by alanb128
You are right, I some how missed to get a release on the OS as I thought the OS would install it by itself 
All services seem up and running, I can find the device in bluetooth and also in Spotify BUT when trying to connect in Spotify it just says "connecting … " and in the log is:
01.07.21 17:22:15 (+0200) spotify [2021-07-01T15:22:15Z INFO librespot_core::session] Connecting to AP "gew1-accesspoint-a-dv19.ap.spotify.com:4070"
UPDATE: I gotta configure credentials lol I should just start reading the whole doc. What if I am using as my Spotify login my Facebook “easy login”? Should I use my Facebook credentials then?