Few comments:
I've checked the licensing, and it's not clear from the webpage;
I gathered that it's not GPL, right ?
Also, using PortAudio means it probably cannot be GPL.
I am uneasy about this statement of PortAudio which makes it not BSD:
Any person wishing to distribute modifications to the Software is requested to send the
modifications to the original developer so that they can be incorporated into the
canonical version.
regards,
junichi