My driver's side front window seems to have developed a life of its own. Will go up when supposed to go down, vice versa and sometimes refuses to move at all or only a tiny bit....normally when it is open and starts to rain

It can still hear a click when operating the button and do have some uncontrollable movement which would seem to indicate that it is the regulator? If so, should I replace the motor as well when getting the job done? OEM or Fleabay?
Also, please could someone confirm the correct part numbers for a front driver's side window motor and a regulator on a RHD 04 S4 Avant.
Many thanks