Complaint about new Polo Vivo bought 2 months ago

I bought a brand new Polo Vivo from NTT Volkswagen Paarl. As I did not even had my car for a month, the radio started to cut out. What I mean by that, is that when I climb into my car to start my car, the radio will come on, but no sound and I cannot use my telephone. I took the car back to the dealer, where they just put in another code into my radio. For a week things went well, and than back to the old story. I took the car back again, and they replaced the radio with a new one. After approximately another week, same story again, and I had to take my car back to the dealer again. This time they took my dashboard and my door covers apart to see if there is any problems with the wiring. Now, not even a week later, the same story again!!!!!!! I was so excited when i bought this brand new Polo Vivo from the floor with only 31 km on the clock with the assurance that i will never have any problems with my new car, than this started to happen. I bought a brand new Volkswagen, why do i have to sit with all of these problems. Surely, if you buy something new, the product/ car has to work. I have a guarantee on my car, so I expect it to be replaced or something. Is that the kind of service i get from a Volkswagen dealer. I am thinking of going to see a lawyer and the bank where we got financed. What happens after a year after my dashboard was taken out? Rattle-ling and so forth? I am very sorry, but I never ever expected this from Volkswagen as these cars are supposed to be the best in the world and i love them, but after this. I don't know. Every person on this earth expect something to work well after it is bought brand new. Than the dealer told me that it could be my phone. Sorry, but if it is my phone, than the radio will do it every time and than Volkswagen have to tell their customers that certain phones are not working on their cars, otherwise it is false advertising. I have send an email to Volkswagen South Africa and still have not received any response.