90% of my albums just disappeared

[Geoff_Coupe]

If they are Qobuz albums, then this is a known issue. The fix has been implemented, but apparently it will take a few days to roll out from Qobuz. See here:

Qobuz albums removed from Roon Library [Qobuz server sync issue resolved]

@Daniel_Haythornthwai & @pascabl — We discussed further with Qobuz. It turns out the fix was implemented, but it will take some time for this to process for all accounts. It is expected that this will probably continue processing for a few more days. Unfortunately, I can’t give specific timelines for specific accounts, but the good news is that this should be fixed for everyone soon. Thanks for your patience again, everyone!