Air re circulation flap problems

Hi all,

I have a 2009 MKII Fabia which has developed an intermittent clicking/clunking noise from the passenger footwell when operating the air recirculation function either through the dash button or when reversing. I have noticed that the air recirculation flap is not operating smoothly, and starting to click either in mid operation or when it is completely open or closed. I am almost sure that the noise is coming from the cogs/gearing attached to the motor which are skipping occasionally as if the flap is not properly aligned. Do I need a new motor/gearing system? Is it easy to replace the motor, or is it a dash out job? And do I need VAGCOM to re-align the flap when installing a new motor?