@kota1 My guess I've owned 75 sets of wireless transmitters and receivers and worked with 1000s. All these systems were professional and expensive usually averaging about $5k each some more some less. If it takes that much money to create a high fidelity wireless system how do they put that level of quality in a wireless speaker, I think the answer is they can't. The companies I dealt with were wireless microphone manufactures, Zaxcom, Lectrosonics, and sometimes Shure.
The problem is not the technology it's the FCC, Federal Communication System, they have to coordinate all the frequencies zooming through the air.