3 Things, First call dealer who sold unit. Second, I would check to see if its the e. clutch make sure all bulletins were completed ( Model year 14's only) Third, Look to see if when Engine is running if the bolt holding e.clutch to crank has a wobble to it causing a viberation in relation of pto clutch and clutch stop. There were some units that the stub shafts were not trued properly. But seeing its BRAND NEW I would let dealer fix it. Also make sure its not a deck wheel viberating making noise.