Last Friday, I was playing at the monthly "first Friday" community dinner that my church hosts. It's a free dinner for anyone who cares to come, and we also provide live music, in the form of piano, played by the church music director, and me. Sometimes people get up and sing along with us, too. Depending on the song, I play either sax, flute, or Coda, usually without a microphone. Coda actually carries much better in the space than flute, as you might imagine.
Anyway, last Friday I had played a few Christmas songs on the tenor sax and was switching to Coda for "O Come Emmanuel," but I found that I was having great difficulty getting the low notes to play in tune. They were mostly way off, and I thought the Coda might be cracked. But that wasn't the cause at all. The day before, I had sliced into my middle fingertip while chopping carrots with one of those "ceramic" knives. The cut was fairly deep, so I cleaned it and put a band-aid (sticking plaster, for our friends in the UK) over it. And I promptly forgot all about it.
So I still had that bandage on my finger on Friday night, and that's why my pitch was off. Once I realized it, I just switched to the flute, which is a closed-hole instrument, fortunately. By Sunday, the finger was healed well enough that I was able to play Coda again.