From a reader:

Bagpipes:
Why do pipers walk around as they play?
To get away from the sound.
A man parked his car and walked away. He suddenly remembered he had left his pipes in the back seat and the window was open. He rushed back, but it was too late–someone had put two more in the back seat.
Singers:
How many sopranos does it take to change a lightbulb?
None–managers do that.
How many mezzos does it take to change a lightbulb?
Two. One to change the lightbulb and one to say, “Isn’t that a little too high for you?”
FYI: At the slightest provocation, I will inflict my Ophelia joke on you.