errrr it happened to me too

u have to pull forward and hold and push - then let go

if its paused then just push button.

 

wait, can u repeat that?, maybee a little more detail

 

My A4 B6 CC:

Pull the arm toward you to reactivate cruise control using the last speed you set.
Push the arm all the way away from you to turn it off (but I don't think it clears the last speed you set so you could pull it toward you again to activate I think)
With the arm in the middle position, hit the button at the tip and it will cruise at your current speed.

Mine works fine.

 

mine wont engage either, i have put it in on, then pressed set and it just slows down