A quartet of talented actors and musicians are bound to make sweet music when put in a room together — but what if the song choice and instrument selection was left entirely up to chance? Jimmy Fallon, Michael Buble, Dave Matthews and Kiera Knightly attempted to play “Name That Tune” on instruments they’d never played before, let alone even heard of. The results, understandably, were grating on the ears — and inspired a few uncomfortable looks from Fallon’s house band, The Roots.