This is an interesting issue.
Using 0.2.1 & 0.2.2. There is no sound regardless of what input source I select.
Using 0.2.2 w/ pref pane, I am able to get sound by selecting the unknown source. However, sound get distorted within 1-2 mins of continuous playing audio. system.log shows that clipIfNecessary() called a couple of time, and sound get distorted.
Interestingly, when I dump the 2 codec and channel output, all versions above produce the same result. Attach is the codec dump from 0.2.2 w/ pref pane.