Has anyone else noticed that Roon won’t work (or works VERY slowly) when Time Machine is backing up. It’s as if Time Machine is hogging the whole network during backups. Anything to be done about that (since TM backs up every hour)?
I noticed that too. I turned off Time Machine in System Preferences. I now just backup periodically (when necessary) by right clicking the Time Machine icon in the Dock and selecting Backup Now.
Is the Roon directory excluded from the Time Machine backup? If not, you may want to try this to avoid the massive file IO operations happening within the Roon directory during a backup. According to other posts on the forum, a Time Machine backup of the Roon directory will generally be corrupt, so there is nothing lost by excluding this from the backup. Roon server (or core) needs to be stopped during any backup operation to avoid corrupt backups.
 See this post , including the note on Time Machine at the bottom