I've been trying for quit some time to get my Xbox to connect to the media on my new D-Link DNS-323..spent hours refreshing UPnP and iTunes without it ever working.

However, I found another thread on the internet that completely fixes it and makes it work PERFECTLY smooth...check it out it will save you from bricking your DNS-323.

Easily install Twonky 6.0.xx on a D-Link DNS 323
http://forums.linn.co.uk/bb/showthread.php?tid=10063