Hi Dave,
You really picked my favorite camera ;). I have this camera myself and it only use AAC which sometimes is a problem for NCS. For some time ago a new free AAC was implemented in NCS that should work. Your results are probably fine and I do not see that you do anything wrong. I have an Edimax camera here and I get the sound correct in the windows client, but that is PCM. Do you have another cam with sound, but not AAC?
I have noticed that for h.264 the system have to work a lot and the audio comes last.
I just had a discussion in another topic with sound not working and it is tricky.
In my last post I did a test on Android and the web client in Chrome. Can you do that test and see what happens.
-Henrik