I use roon with qobuz (studio subscription) around a month (both I am new to). 70% of the time I use them together I have a delay about 30 seconds on starting a track or between tracks. This doesn’t occurs if I play my local tracks.
There are absolutely no ploblems with the qobuz app.
I have a strong cable connection with 400 mB/s, a roon server on an i7 Notebook, all is wired over Gigabit Lan. Playing the songs over a PC with RME Fireface, two Sonos Speakers or iOs devices.
Thanks for help