[65535]

You were never really clear what exactly you were trying to accomplish.
 
The only off the shelf WiFi audio streaming (not media streaming) I know of is the Apple Airport Express which you can stream audio from an Apple device to the Optical/Analog 1/8" mini output of the Airport Express. This is true streaming audio from a device.
 
Other options are sending audio from a dedicated computer to another device over a custom interface such as the rWave from Arcam and other audio streaming.
 
The common option is media streaming and media servers with remote control. That's the most practical way to accomplish remote control of audio and other media. The media exists either on the playback device or a NAS solution and is read by the playback device which can then be output through just about any DAC you can imagine (USB will almost exclusively require an actual computer running OSX, Windows, or a Linux/Unix OS) remote control can be accomplished with Apps or dedicated RF/IR controllers.

 

[MaciekN]

Thanks for the tips, even though I've spent quite a few hours researching this topic I may have just as well gone the wrong route and in the end it may be not at all complicated.
 
If you choose an Android server you can stream audio from a network attached storage to a usb DAC and control it remotely with almost anything, as far as I know if you supply the power for it any Tenor chip based DAC will work but you have limited DSP capabilities compared to PC running Windows. On the other hand Android servers consume much less power so they can be left running 24/7 with little impact on your electricity bill. So USB DACs do not actually need a dedicated Win/OSX/Linux PC. There are also low power Linux platforms such as Raspberry Pi or Beaglebone Black, the former seems to be a popular choice for an audio server with USB or I2s output but people seem to have mixed feelings about the quality and ease of set up.
 
Solutions such as Arcam rWave are dedicated to use with DACs from Arcam, same with similar solutions from Cambridge Audio and other such companies. What I mean is that as far as I know there is no off the shelf stick that would work lke the above with just about any USB DAC. You have to build a dedicted server which may be quite costly, for example yesterday I checked the price of CAPS (Computer Audiophile Pocket Server), and its above 500$. Of course, you may probably get similar results with an old stationary computer that you assign to be an audio server but thats another story.
 
Overall I was looking for a reasonably priced (around 100$) solution that would allow me to use my USB DAC with just about any wi-fi equipped device I have at home, so I wouldn't have to power up my 400W stationary PC only to listen to music. The server I linked to in my last post seems to be the choice with only drawback being that there is no advanced equalizer for Android that would allow me to compensate for the room acoustics or speaker limitations.

 

[65535]

You still can't stream live audio to a USB DAC over WiFi. Best you can do is have a media server and an Android mini-PC which may or may not support USB audio output. 
 
If you went Apple you could stream things to an Airport Express and use an Optical output to a DAC. 
 
 
This might work with an Airport Express and using Optical Toslink to connect to a DAC.
 
https://play.google.com/store/apps/details?id=eu.airaudio&hl=en