The AirEnabler is designed to work with 3rd party higher end USB DACs and USB Speakers.
Note the following:
It's not possible for me to test all USB DACs, so I cannot guarantee that any particular DAC will work. However, below are some that I've personally tested.
A cheap no non-sense DAC. Requires additional USB A to B cable.
A very affordable (~$30) and versatile DAC with RCA and S/PDIF Optical output, but a little bulky.
One of my personal favorites given the compact form factor and price (~$20-30).
Wireless AirPlay to these awesome headphones.
Supports S/PDIF optical out. My only complaint is that the version I received was USB 1.1, which required a USB Hub.
Discontinued, but one of my favorite USB Speakers