I've got a new Yamaha R-N303 receiver that I'm enjoying. Yamaha's MusicCast server is nice for playing files from my home PC, but the interface isn't my favorite. I prefer Plex for the interface. I can use Plex over Airplay, but Airplay only streams at 44.1 KHz. So I was thinking of setting an iOS device atop my receiver as a dedicated audio device in order to use Plex and enable high-resolution playback. What's the best way to send digital audio at native resolution over a cable into my Yamaha? 1. Lightning > ??? > Optical? 2. External (headphone?) DAC and into the Yamaha's RCAs? I'd prefer not to have another apparatus that I have to power and find room for. I'm also having trouble finding Lightning-enabled DACs that aren't meant for portable use or use with a personal computer. All other ideas welcomed. Thanks in advance.