Hey @Michael_Putz,
Ben here with the support team, thanks for taking the time to write in! After enabling diagnostics on your Nucleus, we, unfortunately, found database corruption being caused by a failing SSD in your nucleus.
To put it simply, database corruption means that the records Roon is reading from your database are different from what was originally written. In some cases, corrupt database records can go completely undetected. And it’s only when we release an update that requires Roon to re-scan every record that the corruption shows itself, which is what happened in this case.
We’ll need to get an RMA started for your Nucleus, I will follow up with next steps via a PM. Please keep an eye out for a message from me 