When I bought this, there was no such thing occurring on the test board the previous owner demonstrated. Not knowing any different, when I got it home and setup the drums according to the specs in the manual. When operating the sander, I was only able to move the table up by less than an eighth of a turn. Even then, this ear piercing squeal emanated from the drums. I have 80 and 120 grit papers on the drums. I checked the bearing and replaced two, changed the drum drive belt and ensured the motor was tight. Has anybody encountered this. I'm in the process of sending a video to Grizzly to see if their techs can help me.
THanks for any help on this. My neighbours about 1000' away wondered what was going on??!!