Definitely a rights issue. I've heard Steinberg on Flames Talk explain that some of the audio clips are for broadcast only, because they couldn't buy the rights to include them in the podcast.
Sound recordings are generally available to any radio station that wants them and is able to pay the appropriate fee. I don't think there is any equivalent system for podcasts, so rights have to be negotiated with individual copyright holders. That would get messy fast, and of course the rights holder can simply say no.
__________________
WARNING: The preceding message may not have been processed in a sarcasm-free facility.
|