Why not just start Blender usually, but set the volume of all created factories to 0? You might also be able to set the device volume. I can’t check, though - it seems that Blender’s having some problems.
The whole problem:
Using skype and blender on a linux, ubuntu 10.04 machine causes pulse-audio to do odd stuff. This makes skype sound like darth-vader. In order to get around it I used the -noaudio tag. This works fine.
The problem wasn’t with the noaudio tag, but was with skype. aud was still sending something to the soundcard, and failing because skype was using it. I don’t know why it was still sending stuff when the noaudio tag was used.
You could create a module called aud or another name and use that as your sound library. Then in that module attempt to import aud or return a blank spoof class