Thanks for clearing that up Joey! Airplay works really well and all the song info shows up in my receiver’s display, so the USB port is kind of redundant anyway, at least for music. The neat thing about Airplay is that DPS actually controls the receiver’s volume with the slider which is a nice touch (no pun intended). 🙂
The receiver actually has a browse mode for the USB port, which can be set so the music on the phone gets browsed, similar to connecting to DLNA on my computer. This mode allows the receiver to play back the music from the USB port, including showing song information in the display. Of course, it’s the same as playing it back from my computer, which means DPS isn’t involved.