On my old silver 2,2 from 1981:
3) side windows opening/closing was without clacking in final position
My red 2,2 S from 1983:
3) side windows are clacking in final positions
My wifes yellow 1,6 from 1982:
3) drivers side window is clacking, but passengers no
This noise is because the motor gear housing is not held tight. See my FAQ's.
Roy