WebAudio block?

Hi all!

First post on the list. Beginner with gnu-radio, so forgive any ignorant
questions.

I want to build a “receiver” and later on an “analyzer” for signals i
hear
on WebSDR.org. Does anybody know if a block exists that can pick up the
audio from a web-page (in the case of WebSDR a Java applet or HTML5
code)
and process that in gnu-radio? Or do i have to short-circuit my
audio-out
of my computer to the audio-in and just use the audio source block?

Thanks,

Ton.