Is is one of these?
If so, the manufacturer is Prospec Electronics and they have a series of
troubleshooting videos on their website.
I would see how to unmount it, or get behind it through a cabinet if you can, and make sure a wire didn't come loose. Assuming good connections, try various inputs, if nothing then it's done and needs to be replaced, they aren't repairable.
FWIW, I love these threads on outdoor music, as soon as you mention it everyone immediately assumes it's the guy camped next to them. I added a Kenwood 200w power amp to my PolyPlanar outdoor marine speakers, it cranks up loud enough now to entertain an entire CG. However, I don't use those speakers at a CG, they are for boondocking use.