It seems that all that is a bit outdated now, though; the list doesn't include more modern devices like the 6P, and the software on Android's side has clearly changed from 5 to 6. The information about OTG isn't applicable to USB C, either. If I look at the fact that it worked on Android 5 and via an older USB cable, I'd say that maybe they changed the device type detection in a way that's incompatible with my DAC. The product page specifically mentions that it uses USB Audio Class 1.0, so maybe they removed compatibility with Class 1.0 in Android 6. I compared everyone here that said they got it working. The Chord Mojo that another user here said they got working mentions that the Android device must have OTG support. But the user that got it working with the Behringer UCA222 - that product page mentions USB Audio, but not what class. The user presumably using a JDS Labs C5D, that product page mentions OTG too, and not USB Audio. Overall, all this data doesn't really point to anything in particular, sadly.