It's an easter egg, I'm assuming it's related to the easter egg in the game Terraria, where the duck had a similar sound by a human when it would quack, it has a chance to sound like it, it's possible it could be unrelated, but when I first heard it, that's where my thought process went

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I've heard it! I thought I was crazy lol :D

It's an easter egg. Possibly a reference to a cat with the deepest meow.
https://www.youtube.com/watch?v=w7x_lWJNnNg

So funny!