Hi again, I think you’re connected to the wrong audio device. By that I mean the Airplay coonection to your SHD rather than the Roon RAAT endpoint. This looks to have the answer to your issue: Advice sought, Airplay vs Nucleus? with a picture or two. You need to look under Settings >> Audio to manage your endpoints. Good luck 
and feel free to update if you’re stuck or just to say it’s working.