Help with Nexum Tunebox 2 (TB20)

I recently acquired the above device and want to use it to as a streamer from my Android (LG G8) phone. For whatever reason, I'm having the damndest time setting it up--there's no Android app or online manual and the manfacturer is wholly unresponsive. The device appears to use DLNA for Android; when I turn it on my phone indicates that internet isn't available on the Tunebox wireless network.

Any connection help you can give would be greatly appreciated!!