Audio and video installation service near North Augusta, SC

Purchased a subwoofer and amp that they recommended and let them do the install to ensure it was tuned correctly. a couple days later the amp starts cutting out so I go back. they tell me that the remote wire is loose and it’s fixed. Not even a week later the issue comes back. I take it to them again and they tell me they’ll look at the amp but if there’s anything wrong with it it’s my problem to file the warranty.. Also, when I purchase these items, they waited until they installed the amp to tell me the speaker that I bought will not fit the box I have and then I’ll have to buy a new box because they can’t take the amp back for me to get a different speaker. So I agree to buy another box then they tell me all the boxes they have only have 10 inch holes and I will have to pay an up charge to have it cut to 12 inches. TERRIBLE SERVICE