It’s a bit of a Linn myth that the two parts of the Linn bearing are a matched pair - I guarantee they are not. Also, the Cirkus inner platter is identical to the pre-Cirkus one, only the part of the bearing that fits to the chassis is different. However, the Mober bearing is a very odd design in that it has chosen to use twin ball races - frankly, this is entirely the wrong choice in a turntable bearing and will be very much noisier than the shaft and journal type Linn use (also the majority of all turntable manufacturers use a variant on this type of bearing). If you can hear a grinding with your ear then the actual noise being generated must be huge relative to the noise of the standard bearing.