From The New York Times:
Seven years ago Reginald King was lying in a hospital bed recovering from bypass surgery when he first heard the music. It began with a pop tune, and others followed. Mr. King heard everything from cabaret songs to Christmas carols. “I asked the nurses if they could hear the music, and they said no,” said Mr. King, a retired sales manager in Cardiff, Wales. Last year, Mr. King was referred to Dr. Victor Aziz, a psychiatrist at St. Cadoc’s Hospital in Wales.
Dr. Aziz explained to him that there was a name for his experience: musical hallucinations.
More here.