Verbally abusive over the phone and in person

Bought some speakers and head set for my car. 1 of the speakers in the set wernt working. when i had phoned to report this he said he could not help me. I then went to the store with the receipt and the owner spoke to me first telling me that he's not responsible for me buying something thats not working even if i had my receipt. When i told him i want to return the goods he then became verbally abusive telling me to just f off from the store or he'll get his boys to throw me out. <br> <br>