Ok, so I signed up here to answer your questions! :)
I'm the developer of USB Audio Recorder PRO and Audio Evolution Mobile for Android.
My USB audio code completely bypasses Android to get rid of all its problems and talks to Linux directly using file descriptors. That's why there are no limitations in that respect. The only problem is that this is user space code (and technically not even a driver) and does not run at a real-time thread priority. For DAC's this is no problem since you could increase your buffer size to avoid glitches, latency is no issue for playback only.
I know there is still some work to do with some buffer sizes not working etc for some DAC's and yes, there are reports of 96kHz not working, but give it a couple of weeks, this is just an initial version!
The app wasn't originally meant for DAC's either, but as a pro recording solution, but if time permits I can add playlist functionality as well.