I’m running Roon server on my Fedora 34 desktop and every time i boot the machine Qobuz is not working properly.
It gives a connection error on the iOS app about Qobuz and it either can’t play anything at all from Qobuz or does not find favorite albums and artits but i can still access them by searching manually. This problem occurs 90% of the time after booting the system.
The only way to fix this is stopping the server, emptying /var/roon/RoonServer/Cache and then restarting the server. Sometimes this also does not work and i have to do it again.
I can’t be sure when it started, i barely had time to sit and listen from the start of the year to like maybe a month ago. For a while i had just been doing the steps described at startup without thinking much about it, it became routine. Anyway i just tested it and it seems to work now so perhaps it was the issue you described. I will keep an eye on it and see if it happens again.