I downloaded and installed USB Audio Recorder Pro Trial and tried it with Minix Neo X7 and FiiO E07k.
First try was disaster: the X7 crash & froze. I had to eventually reflash the ROM.
The second try was great success: I can inform you that UARP works with E07k. I tried both mini-USB OTG cable on mini-USB port and normal USB cable on regular port. Both ways worked equally good. I played some FLAC files as long as trial let me.
Oh, and UARP worked with my unrooted (older model) Nexus 7 and E07k through mini-USB OTG cable.
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