Carl if you take the bike off. gently spin the flywheel, it should be perfectly quiet. If it sounds grinding, its likely its picked up tiny hard particles inside the flywheel. The clearance between the flywheel and magnetic coils is less than 1mm, so little bits will cause a grinding noise.
You can get a flywheel puller from Tacx to do the clean up
You can get a flywheel puller from Tacx to do the clean up