The conveyor belt on the drum sander was over tensioned on one side. This drives the belt to the opposite side. The belt should travel evenly, in the middle. The belt is getting damaged on one edge, and it may be stretched out on one edge. It was replaced just a few weeks ago.
If you are not familiar with the equipment, please do not be making adjustments. If you believe that a piece of equipment needs adjustment, report it using the red QR code, found all over the shop.
Thanks