Hi Eric,
Thanks for coming back to me, I had a bit of time at work this morning and scoured through the support forums and found a previous similar problem, where the fix there worked on mine too just now.
It was this one by the way - Roon Won't Enable Audio for Devices Connected to My PC
For now it all seems good, the RAAT folder didn’t do it but when the Realtek driver was uninstalled it immediately started behaving.
Elliot