If it’s going to be covered at all, I would just get a cheap-ish sound bar with Bluetooth connectivity. Getting anything that is “waterproof “is going to be very expensive.

My dad has a TV outside that is only covered by About three feet of the roof extending from the house. He keeps it covered when it’s not in use, but it’s going on at least four years and it’s going great. I’m pretty sure it was a $400 TV from Best Buy.

I’d go to Costco, and buy whatever sound bar fits your budget.