Windows open/close in bits
 

Hi my windows on my 1992 Golf GLi don't go down or up in one go, it takes about 5 clicks of the button as it goes down in bits. I have only just got the car so i don't know if this should happen or if its a fault, the motor seems like its working good because it doesn't slow down before stopping it just goes and stops and this happens on both windows.

How do change it so that it goes down like normal? thanks.