If there’s no specific reason you haven’t updated to Monterey 12.1 I’d start there. Also, when you say you’ve removed the app and reinstalled, did you also delete ~/Library/Roon ? If not, try renaming that folder (e.g. Roon_old) as that will remove your previous settings for the app. If that works you can delete ‘Roon_old’. If not, to return you back to where you started, delete the new ~/Library/Roon folder and rename ‘Roon_old’ back to ‘Roon’.