Ira Glass says:

In an edit of Gabriel Rhodes's story in last week's show, I asked him to insert erronenous information about sound waves and electromagnetic waves, and then acted so completely confident about it - misremembering a science show I worked on years ago - that nobody in the editing process bothered to fact check it. This was very much my mistake and not Gabe's, and I regret telling him to insert a mistake into his otherwise carefully researched and fact checked story. Thanks to the many listeners who wrote to point out the error. We'll go back and fix this, so the version of the show on the website in a few days will have the correction. He was using electromagnetic waves, not sound waves, for his experiment.

Also, I fail typing. ("Electormagnetism".)