Our Machinew was kind of doing the same thing. It turned out the belts were bad. Put new belts on good as new. If memor serves me core try it is a 5-5ms-730 bando belt. You use a set 1 is 2 ribs and the other is 3 ribs. A bando dealer in Ohio sells them for like $40 or $50 bucks. Kitamura wanted $250 for the set.