The book Sweets: A History of Candy by Tim Richardson refers to the "Sound Bites Lollipop" produced by Cap Candies circa 1998, a lollipop that supposedly contained a radio. It was developed by Andrew Filo. The battery-operated device sent vibrations through the lollipop stick, so when you bit down on the candy, you could hear music inside your head via bone conduction. That means that when you bite down on a Sound Bites lollipop vibrations travel through your teeth to your jaw bone and then inner ear, so music sounds louder inside your head.
It contained no radio (though it easily could have). There were six different versions of Sound Bites. There were three musical themes sporting guitar, drum and saxophone. Then there were three special effects versions: cartoon voices, space noises and "fun" voices. The device had four buttons that, when pushed, mix and match the sound selection. But all these was built into a "holder." You could stick basically any lollipop into it. More here.
Press started in Februyary of 1998 following a toy fair in New York, and was distributed nationally by May, and globally by the end of the year. It retailed for about $10. the gimmick was written up by the LA Times, New York Daily news etc. It was trumpeted as the harbinger of the new "interactive candy" market...whatever that means.
For what it's worth Andrew Filo got the idea on a tour of the Thomas Edison Museum. Filo learned that the Edison, who was nearly deaf himself designed a device for the deaf to listen to his phonographs via a "bite bar." The book Edison: Inventing the Century by Neil Baldwin records a story from his daughter Madeleine "Sometimes her papa would put his teeth on the piano — literally bite it — so that the vibrations resonated through his skull bones... Edison's personal Disc Phonograph, preserved in the laboratory, also shows teeth marks on it's soft wood framework." With 2,332 patents worldwide I've found it challenging to locate the specific patent in question but it's plausible.