Hi @Neil_Collis,
So we can better assist you, please provide a brief description of your current setup using this link as a guide.
Make sure to describe your network configuration/topology, including any networking hardware currently in use, so we can have a clear understanding of how your devices are communicating.
When you try to login to TIDAL in Roon are you receiving any errors? Have you tried rebooting your Core machine since you’ve installed Roon?