A Duck's Quack Doesn't Echo and no-one knows why?

I came across this trivia/pseudo-scientific claim/urban legend a few times. heard it on Class 95 radio one morning as a soundbite. first saw on the ticker display in a NEL MRT station showing quotable quotes. this might sound plausible at first, but on deeper thought defies phsyics.

googled the reference, and out popped urban legend sites debunking this claim. Apparently, this claim had surfaced everywhere, even in the UK. Prompting the Accoustic department of Salford University in Manchester to actually put a duck in an echo or reverberant chamber to accurately measure the accoustics of a duck quack. Turns out out that a duck quack does indeed produces echoes.

so why did this myth came about? the researchers considered a few possibilities. That a duck quacks too quietly, so the reflecting echo is too quiet to hear. Maybe ducks don't hang around reflecting surfaces, like a mountain, buildings or concert hall for the sound to bounce back.

now I feel like calling Class 95 and NEL...

(Daisy the reverberant duck was not harmed in anyway and was retired to a farm after the experiment)