[Vidal]

You need one of these knock off camera connectors from an auction site of your choice: -
 
http://www.ebay.co.uk/itm/iPad-4-Mini-Camera-Connection-Kit-Dock-Connector-to-USB-Host-OTG-Adapter-Cable-/201243960087?hash=item2edb132317:g:WXAAAOSwq7JUJMuG
 
Simply cut the white cable and trim the sheath back to expose the wires, then do the same with a USB cable (micro,mini,Type B).
 
Solder the of the CCK to the corresponding colour on the USB cable - red to red etc.
 

 
Wrap up the soldered bits in shrink wrap or insulating tape, as below.
 

 
Then wrap cable in plug in whatever shape suits your DAC - in my case the Fiio K1 as seen in the picture below of one I made earlier.
 

 
I'm sure others will do a better job of the cable soldering. The upshot is you have the DAC connected to your iDevice without a bulky CCK and cable.
 

 

[Vidal]

I just had a new batch of CCK cables these don't have the USB cables coloured correctly. Red and black still apply but green and white are now grey and white respectively.