Hi @Ben_Katz,
Thanks for the additional information! Based on your report above, I believe you may be experiencing a known issue tied to Various Artists and fluctuating album amounts, here’s the tracking thread:
With that, your extensive library of 780k tracks does put some extra demand on Roon’s performance, and although we strive to test across various setups, extremely large collections can sometimes present unique challenges. We know this may be disappointing, and our development team is always seeking ways to optimize for large libraries. Thank you for your understanding.