Hi Azz,
I'm not sure what type of A2 you are driving. If you can find the time, please fill in your Public Profile. European cars in general are not having a good time with their suspension components and the A2 is no different. Knocking sounds can come from various sources including anti roll bar mounts, drop links and shock absorber / bearings. The drop links are relatively cheap to do. I presume that you have not had the car from new, but at seven years old it is entering middle age, when wear and tear starts to show. I also see that your other recent post is about Koni shocks. The Konis transformed my car. I am not one for lowering so I still have the standard springs.
John.