Bronisław Huberman

Bronisław Huberman was a famous 20th century violinist and a friend of the Fourth Doctor.

He owned a Stradivarius violin, which was stolen from him in 1936 after he performed at Carnegie Hall in New York City. Even though the Doctor and Leela managed to find the thief, they did so after Huberman's death, and so they were not able to bring him back his instrument without disturbing the timeline. (AUDIO: String Theory)