Sansui 6200

I have bought a surround sound system for R5.500 including a 5 year guarrintee.Installing the system the DVD player didnt work so i discovered the 2 pin plug is broken so i removed it put a 3 pin plug to get the player working then the player didnt pic up the DVD.I unplugged it took it back to the supplier which told me the warranty on the system is gone because of the plug .IF i want to exhange something i must repack the whole system and bring it back.I really think its poor service how can i refer people to do buissines with them .i am certanly not happy with this service and will defenitly take further if i dont get respoinse.I want to reclaim my money which i have paid for that extra guarrintee.