Hey,
The JAB 5 has high potential, but I’m not 100% satisfied.
It has a Ground noise that you can ony avoid if you listen Loud enough. I’v riten to Wondom to ask for Help and even send them a Video demonstration you can take a look at.
In your case I think you can use a simple dac like the pcm5102 and hook it up to any Wrover Board or you take a ESP32-A1S (Battery system is a danger) or any other mentiond on the Squeezelite Github.
That would be the Cheapest and most ecological Solution for your setup!
Would be great to see some photos of how you setup your speaker and Amp.
Greatings
Axel