Sometimes DACs, or amps with DACs or AVR's vary in their ability to play certain format types depending on the particular input being used.
How are you connecting your phone to play these files? If you check your manual's appendix it should state the format types and resolutions it can play for each input. If you're using a front usb input for instance that doesn't play, you may find that using a DLNA compliant hard drive with the same tunes via a rear USB input might work. Also, I would imagine that your phone is not DLNA compliant, so it's unable to communicate the files with your AVR.
I'm only guessing here, but unless someone has the exact same issue as you with an identical receiver, then nobody would likely know. So I can only suggest checking your manual thoroughly. Look for the file types and resolution your AVR can process. Then look for a device that's DLNA compliant that can be connected to your AVR.