I used this on Windows to stream over Wifi to my Android phone:
http://ajeetv.info/wifiaudio/

Using the Window client the other day it worked well, although with some minimal occasional stuttering, and maybe using a little more CPU on the phone than I'd like.
I tried the Linux client today on Xubuntu 15 and audio is not getting through to the phone for some reason.
Hmm maybe I can try the Windows client through Wine?

What are your experiences with streaming audio over Wifi?
You'll need 300Mbps at least to get decent results. I am sure that would be an overkill, but you won't have any headaches with delays. Get a decent AP that is meant to handle media streaming. No Dlink or Belkin please.
The delay is minimal, it did not bother me personally.