I suggest
    1. That you check all the linkages between the wheel and the rudder stock. Not familiar with a 42, but mine has a “motor bike” chain between wheel boss and first quadrant with a rigging screw in it and this needs periodic tightening. There are also a number of other linkages which require regular inspection and greasing (at least) between the wheel and the head of the stock.
    2. And, the rudder bearings themselves can be tightened by unscrewing a grub bolt, tightening the “nut”, actually a circular plate with a horizontal split in it, and then retightening the grub bolt. I have found this necessary every 1000 nm or so. The procedure is described elsewhere on the forum.