According to multiple sources at the Boston Philharmonic Orchestra, the first chair flautist was just whistling.
“His lips never touched the flute,” said audience member Keisuke Honda. “I was sitting close to the stage, and it sounded like the performer was whistling, and not playing his instrument. He almost fooled me, but it was easier to tell when you looked closer.”
“At first I thought he had a particularly tight embouchure,” said fellow concert-goer Kostas Mitroglou, who was equally confused. “But as soon as I heard the wind section’s solo, I knew he was just whistling. His fingers were all over the place, too. It became pretty clear he wasn’t even trying to play any notes."
Towards the end of the concert, audience members reported that the flautist had set the flute down to itch his nose, but just kept on whistling.