This video has emerged from a concert which took place as part of the North Shore Chamber Music Festival in Chicago in June 2017.

Violinist Vadim Gluzman and violist Paul Neubauer perform Mozart’s Sinfonia Concertante with the ProMusica Chamber Orchestra conducted by David Danzmayr, when Neubauer’s tailpiece snaps, and a piece of it flies into the audience.

It is likely that the Neubauer’s instrument misbehaved due to the scordatura tuning suggested by Mozart, in which the viola is tuned up by a semitone in order to sound more brilliant in the E flat tonality of the piece.