I have found the adapter to work well. My DAC shows the input as 16/48.Not 16/44? I would have thought Redbook was possible (assuming you had it stored that way on the iPhone), but I've never seen a 16/48 PCM format.
Questions about digital audio output from iPhones
I was trying to figure out how Dragonfly DACs could work with the analog audio output from an iPhone; apparently, the answer is Apple's Lightning to USB Camera Kit, which allows you to output a digital audio stream to a USB DAC (please correct me if there is another way to get digital output without the Camera Kit). Does anyone know what kind of format(s) the iPhone can output this way? Can it output SPDIF, DSD or PCM? Or is it some proprietary Apple digital audio format?