Out of curiosity I looked up if AOMAIS has any new speakers. I might upgrade to a pair of these for $49 each: https://amzn.to/2UzfQCL
AOMAIS Life 30W Bluetooth Speakers, Loud Bamboo Wood Home Audio Wireless Speaker with Super Bass, 3EQ Modes for Home, Outdoors Party & Subwoofer
It's not waterproof like the other one, but it's a bit smaller (no handle). I can build a little hanger off the cross beam to install them upside down (for button access) and angle them down better. 60W for $100 is about as good as it gets, no?