Using the ReadyNAS Ultra 2 as a Squeezebox?

Hi!

I have a ReadyNAS Ultra 2, and I'm using it as a media server.

I just read this post:

http://vortexbox.org/content/149-Logitech-SqueezeBox-replacement-for-under-30

Here the author explains how to use a Pogoplug as a squeezebox. The Pogoplug is a kind of NAS, but here it is modified to be used as a Squeezebox and function as a receiver with line out to the stereo. My question is if anyone knows if this is possible to do with the Ultra 2?

In other words: Is it possible in any kind of way to set up the Ultra 2 with a USB DAC and play directly to the stereo? The reason I want this is that I don't want to depend on having my PC plugged into the stereo all the time. (Yes, I do know about other solutions like Sonos or something similar, but I am looking for a possibility to do this with the equipment I already have)

Really appreciate help with this as I am pretty stupid when it comes to this.

Thanks a lot!