It's possible or the arm of the RRU has slipped. I recommend conducting the dockside setup of the RRU and even before running the Rudder Test, go back to the standby screen and look at the rudder display. If you setup the center last it should be reading zero. Then turn the help one degree at a time checking for good feedback both directions. Account for each degree it shouldn't skip degrees or suddenly jump hard over. If the rudder reads good the go back and run the rudder test and see how it turns out.