Could be the carbon brushes,although the same brushes are used for the drum rotation and spin.Usually if there is a brush problem, the motor will not turn at all, although if they are on the limit of wear,it can be intermittant.
Check the brushes. This is not easy.Be patient.
SWITCH OFF THE POWER TO THE MACHINE.
Remove the dispenser.Remove the 2 screws behind.Undo the 3 10mm bolts behind the door.Swing open the front panel.Pull off the motor connections.Remove the 2 screws & pull off the motor cover.Undo the 4 screws & pull the brush module off.If the ends of the brushes are NOT shiny, & are very short(approx 2mm),then the brushes need replacing.
When fitting new brushes,push them into their holders BEFORE re-fitting the module.Be very careful to align the 4 pins of the module.After fitting,push the brushes to release them(so they touch the motor).
It is unlikely to be a power module fault.
Bernii
February 2008