I'm travelling now, but I've loaded my phone's library from my laptop and I'm playing to a JRiver IdPi connected to a soundbar.
On the phone, I'm just running JRiver for Android.
On the PC, MC can open that library from Playing Now (section below).
Also on the PC, I can click on the renderer in Playing Now and play to it.
Working perfectly. Sounds great.
I've also played Cloudplay from the laptop to the same renderer today.