Ultravox

Ultravox were a pop group in the 1980s.

Professor Grisenko was a fan of theirs, and listened to their cassettes whilst serving on board a Soviet submarine. When finding out that Clara Oswald was from the future, he asked her if they break up. (TV: Cold War)

Behind the scenes
Although Clara didn't answer Grisenko's question, in the real world, Ultravox did split up in 1988, 5 years later.