I’ve just successfully migrated my Roon Core onto a dedicated machine, but I would like to continue to use the Roon Controller app on the old machine (2014 iMac 5K running Mac OS Big Sur) as a local output device.
When I first fired up the app after completing the migration it told me, as expected, that I was not allowed to run two Cores and to click ‘go back’ in order to connect to my previously set-up Core (which I took to mean my current active one, running on the new machine). When I do this the app appears to hang, with the Roon icon in the middle of a blank window.
I tried deleting and reinstalling the app, whereupon it asked me to sign in, but after that the above was repeated and the app hung again.
I recently installed the Roon controller on a new MacBook Pro, and there was no issue. Upon first launch it asked me if I wanted to set-up a new core or connect to an existing one, and I connected to the existing one. Something is evidently different about the iMac due to it previously being set-up as the Core, even after a delete and reinstall of the app.
Did you follow the guidelines on Migration in the FAQ? The last section is:
Previous Roon Core
Once your new Core machine is up and running, you can continue running Roon as a remote on the machine that previously ran your Core. It is important that you “clean up” the machine that was previously running your database. You do not want the same database running on two machines . We recommend renaming or deleting the Roon database folder on the machine that previously ran your Core. You can find the Roon database folder here.
I would suggest uninstall Roon on the old machine and getting rid of the old directories (follow the link above). Then install Roon again and during installation choose to connect to your new Core rather than set the machine up to be a core.