As Rowan has said, pipe cleaners can be lethal. Here's what you do - get an egg cup and fill it with water, add two or three DROPS of detergent and mix. Then sneak up on any unsuspecting budgie and yank out a tail feather. Dip the feather in the very dilute solution of detergent and 'paint' the inside of the windway. Leave to dry. Problem sorted (except for those unfortunates who actually do drool to excess - in which case I would advise against playing in places where they serve bacon butties). You can hit the sound-producing edge as many times as you like with the feather and you will not damage it.

If you have patience, you could always wait for you budgie to moult. Flight feathers will do as well - any feather with a 'spine' to it. In extremis, a bit of thin card, cut to shape, will do the job once but feathers can be re-used.