The person who sent this letter is drunk or it's a joke. How do you copyright something that is own by the public in the public domain? (Assuming we are talking about public radio streaming)
"Copyright is a form of protection provided by the laws of the United States (title 17, U. S. Code) to the authors of “original works of authorship,” including literary, dramatic, musical, artistic, and certain other intellectual works. This protection is available to both published and unpublished works."
Anyone with an IQ two higher than a tree can see that over public air waves on a public owned radio is not in any way shape or form a "...original works of authorship..."Nor is it "...literary, dramatic, musical, artistic..." and it certainlyisn't "... intellectual works..."
Talk about grasping at straws.