Disgusting service

Totally disgusted with the service at Gadgets Geeks, Cornubia Mall! I bought an IP Camera for R900 in good faith, only to find that it is faulty after extensive testing. I have asked them the next day to replace the unit and get a new one from their suppliers and they refuse. The units sell for R699 on and Electromann SA, who is their supplier after further investigation. They (Gadget Geeks) accused me of lying stating that I don’t know what I am talking about, and trying to make out that I am stupid. Unfortunately for them I have a highly technical background when it comes to electronics and they are seriously barking up the wrong tree. I have demanded to speak to the owner of the store and he will not engage with me. They will not give me a refund, or furthermore not replace the unit which is supposed to be under warranty for 12 months. Out of principle I will not let this go to rest and I am will go to the ends of the earth to bring this company down.