SoundStories was a group that produced original audio theater for a few years back i the early 2000s.. Here’s one of theirs that won a Mark Time Award for Best Science Fiction audio back in 1999. It was written by Brian d’Eon and directed by Jennifer Arave. –
407 Arachne, Act 1 and
407 Arachne, Act 2
(each 30 minutes).

There is much more free audio on our SideTracks page, too.