Experiment proposal: Use CC-BY-SA for some recordings, and other licences for other recordings. A year later, measure how many copies of which recordings are available on internet. (I don't recommend it seriously, but I would actually like to see the results.)
Hypothetically, would it be too big problem for you to use different licenses for audios of different articles, based on how the article author feels about this topic? Yes, your competitors could legally take some of your audios, but not all of them... so their satisfied customers would then come to you for the rest. Depending on numbers, the gains could outweigh the losses.
If you've been following the announced partnership between LessWrong and Castify, you'll know that we would like to start offering the promoted posts as a podcast.
So far, everything offered by Castify is authored by Eliezer Yudkowsky who gave permission to have his content used. Because promoted posts can be written by those who haven't explicitly given us permission, we're reluctant to offer them without first working through the licensing issues with the community.
What we propose is that all content on the site be subject to the Creative Commons license which would allow content posted to LessWrong to be used for commercial use as long as the work is given proper attribution.
LessWrong management and Castify want feedback from the community before moving forward. Thoughts?
Edit: EricHerboso was kind enough to start a poll in the comments here.