Mu-so Qb 2 silent Spotify connect

I have an issue. After a while not using my Mu-so Qb 2 it is impossible to get any sound out of it. When I try to use Spotify Connect I can see progress of the music playing in Spotify but no sound from the Mu-so. After that it is impossible to get any sound from the system (radio, AirPlay, etc. ). Only option to pull the plug and do a hard restart.

Exactly the same issue as this:
https://community.naimaudio.com/t/mu-so-qb-no-sound-when-using-spotify-connect/25548

Any suggestions? Really annoying and on the limit to sell the piece if no solution.