Here are my GNURadio companion graph files for the HydraSDR RFOne receiver. They are based on the demonstration FM receiver in this tutorial. Hack them, enjoy them, share them.
You'll see two files:
- Hydra_fm_rx.grc is the basic demonstration graph file
- Hydra_fm_rcv_stereo.grc is the stereo version of the receiver
Here's a quick and dirty video of my development of the graph files.

Note: you must install the HydraSDR forked versions of the rfone_host tools before working with GNURadio companion.