Faulty Tablet

I bought a combo tablet deal at Hi Fi corp in Baywest mall that consisted of two tables. When i got home the one didnt work. They replaced it and the new set also didnt work the replaced it again and it also didnt work. Then they said i must give the set back and take another tablet. So i lost out of the two tablets and only got giving one a Telefunken. Once we got home and opened it and installed apps we found out the speaker was faulting and could not hear anything because the speaker distorted so badly. After complaining again and waiting a week for them to come up with a solution the tablet fell and the screen cracked. Now they say that they would take it back because of the faulty speaker and replace it because the screen cracked the warranty is void and there is notjing they can do. So after having to go back and forth to the store with faulty tablets they have now said sorry theres nothing the can do about it! Now i sit with a broken tablet of R900 that i must pay off. It is absolutely ridiculous! If they had given me a proper working tablet there wouldnt have been a problem. But because they sell faulty stock its now my problem