Not sure what the Mojo config is but I did the following steps to set up the Aune on the Pi:
- Plug DAC into USB on Pi and boot/reboot
- Login into the Pi (account=tc, password=piCore)
- Enter: /mnt/mmcblk0p2/tce/squeezelite-armv6hf -l
- Copy the USB device (Aune was iec958:CARD=DAC,DEV=0)
- Goto the PiCorePlayer website
- Goto Squeezelite settings
- Select Audio output to be USB
- Paste the copied string into Output Settings
- Save/reboot