portable devices that can sync with a Wiim Amp Pro

[TimEch]

I currently have 2 Amp Pros in different rooms. I used the Sync feature to play the same source on each at the same time. Works great.
I am looking for a portable speaker (battery powered) to use on our patio that can sync with either of my Win Amp pros (so that the source can play on a Win amp pro and this portal speaker outside on our patio). Running wires and electric to the patio is not an option, which is why I am looking for a portable, battery powered speak. Does anyone know if this exists?

TIA

 

[Mr Ee]

Welcome.

All I can think of so far is any portable speaker with an aux in (or optical in if possible) and a wiim mini powered by a battery pack.
Or just turn one of the amps up loud