Well, as anyone who has heard me perform will attest, I am the most unmusical Mudcatter possible but even I have no difficulty getting a (usually off-key-but that's me) sound out of a kazoo. As everyone has said...(puts on Lauren Bacall voice): "Put your lips together and hum....you do know how to hum don't you?".
Apologies to scriptwriters of "To Have and Have Not".

RtS