Years ago, I had a keyed simple flute. The keys stuck down when the pads got damp, so I kept a little tin filled with talcum powder and some Rizlas in the flute case, sprinkle a little talcum on the paper and close the key on it to unstick it.

Until one day I was just about to unstick a pad when "'Ello 'ello 'ello" and a hand on my shoulder. An off- duty copper in the room. I had to let him snort a great fistful of the powder before he conceded my innocence.