I don't use Spotify enough to justify signing up a plan, so I stick with the free account (up to 10h per Month).
Still, I wanted to stream to my Stereo via Squeezebox.

At getjamcast.com I found a software that installs a virtual soundcard that captures whatever goes to the speaker of the Computer and makes it available via an http/mp3 stream.

Works nicely.

Unfortunately, this software expires after 14 days (now).

Do you know an alternative "virtual sound card"?

The waveinput-Plugin requires the SBS to run on the same (windows) machine, if I understand correctly. That's not the case here :-(