owner attitude and bad customer service

bought sound equipment from supplier. they sold me the wrong stuff, took it back and with hassle he refunded my mixer and sold me a behringer interface for R3000. got home and product was faulty. took it back next day and he shouted at me in font of others and told me im waisting his time and he doesn't want to do business with me. i spend over R8000 there in 2 weeks. they also sold me a samson mic with software and the install cd is faulty and bent this was R2000 and i cant use the mic or software. the interface from behringer was already taped with selotape and i think it was opened before he sold it to me. they put the faulty behringer back on the shelf. i was never humiliated like that in my life. he is rude and many people i spoke to is complaining and we have nowhere else to go in welkom. something needs to be done please cause i'm still sitting with samson mic and software that doesn't work and i cant take it back im to scared cause he shouts at me but his salesperson sold it to me and he told me i'm waisting their time and get out of his shop. spend thousands there and is very unhappy. had an incident with then 2 years ago as well.