🔊🎉Today, February 1, 1985, Shellback was born Karl Johan Schuster, in Karlshamn, Sweden. In 2014, Shellback co-produced ‘Problem’ by Ariana Grande and Iggy Azalea, alongside Max Martin, Ilya, and Peter Carlsson. The song peaked at no. 2 on the US Hot 100, in support of Grande’s second studio album, “My Everything.” The song has since been remixed by Wayne G, DJ Buddha, DJ Class, and more.