what he said.Sorry, I misread your post. My original reply still stands for Griffster.
Regarding your DAC, it is not an iDevice DAC like the Sony PHA-1, Fostex HP-P1 or V-Moda VAMP, so you will never be able to connect it to the DAC portion of your device. You can still connect any portable music player to it via the line-in. If using the headphone out on your music player instead of an LOD you need to have the volume up fairly high on the music player.
If you want to use your idevice as a pure transport and bypass its dac and amp you need the sony pha1, fostex hpp1, verza, godapx, hifim8 or clas.
This is using a 30pin to usb-a lod.
The one you have now ibasso zero connected via a 30pin lod to mini 3.5 will only bypass the ipod amp.