While I just argued that the act of podficcing adds "fannish value" to a work, I'm unsure that readers must obtain an OK from the writer to make a recording.
Since I'm a newbie, I did some research. While I don't think it's possible for a podfic to fundamentally change a source in the same way, I started with remixes, since there's the same "permission" issue there. It seems most remix challenges are based on a mutual remix: by participating in writing, each fan also permits their work to be remixed (with one "safe" work held inviolate).
The
Fanlore Wiki told me:
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Though remixing in both fanfiction and vidding has become enormously popular, not all fans embrace the concept. [... snip ...] Though some fans feel any story is fair game for remixing, others believe that permission should be gained from the author first before using their work as a jumping-off point. Many fans feel it's hypocritical to reuse the original creations of the copyright holders in the canon while protesting that anyone should be allowed to remake their fanworks.
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Current metadata don't state whether the podfic's reader has the writer's permission. Would the absence, permission or refusal of writer's OK change how you'd choose or read podfics?