[User 224999]

EDIT: Actually scrap that. Getting a lot of skipped tracks and pauses between tracks (played 3 tracks and then rest of album was skipped one by one after a 10 second pause each). 1.1.24 didn't seem to have as much of an issue.
Getting repeats of these errors in the log: https://pastebin.com/raw/J2akZTdF

Hmm, interesting, so my attempt to fix the issue actually made it worse. I will try to contact the Kodi devs maybe someone can give me a clue what is going on. I clearly see deadlocks as if the Kodi GUI thread is shared with python. So, you try to play a track but the web proxy (which is hosted inside the python add-on) is unavailable.

However, the passthrough audio via spotifyconnect is working well.

I'm not suprised. In that case the audio is pumped to the speakers directly by librespot, bypassing the proxy to kodi.