Runs fast for a few seconds , then runs very slow

I had the same problem and fixed it.

1. I took it apart, unplug unit, remove the small black cover inside the stand portion, 1 screw. Underneath you will find four screws with a white plastic wire junction.
   
2. Loosen two screws and remove the black and brown wires which connect to the control panel with the dial attached.
3. Remove rear attachment cover, front top cover, and front delonghi cover.
4. Remove top three screws where the blender attachment goes. Now remove the aluminum cover that covers the entire top.
   
5. Slip belt off. Remove three screws with plastic washers that attach motor to chassis.
6. Remove 2 torx screws that are located next to metal bar that keeps top half from swinging too far from bottom half.
7. Now you can pull the motor out and the control panel with the dial. Remove the three slip on electrical connections on the control panel and reinstall. Carefully remove the two slip on electrical connections on the motor and reinstall.
8. Re-assemble and test unit.