2018 400r with 20 inch shaft (sportmaster).
Recently had the 100 HR service done and the tech made a note that the oil was very low (somewhere around 3-3.5 quarts low). I just bought the boat and know to check the oil but the previous owner obviously didnt. Before the service (when the oil was low) the supercharger whine was very loud on takeoff and at wide open throttle.
After the oil change, the supercharger is now completely quiet.
This had me a little curious as to how it was possible and why the motor wouldn't have thrown a code.