I have the same problem here when I am on my laptop with WI-FI. On my desktop connected to my LAN, it’s perfect.
When I am using a Windows iTunes server everything is perfect with my WI-FI even playing the mp3 from a network drive. The problem only happens with mt-daapd.
I’m using version 0.2.4 with iTunes 6.0.5.
I did the Ubuntu Howto from the wiki to install it.