Hello together, I heard during braking that my brake system starts to quichen… I assume it comes from behind was not at the workshop before I went there I wanted to ask you. Has one of you already changed the brakes front or rear ( ceramic system ) and have for me a cost idea what would cost me individually discs and receipts in the purchase Have you also an alternative from which sides you can buy the which brand you can take the originals of Audi from the guidelines. Now thank you very much.