Nope. It's something hardcoded into the func_regenerate. More valve silliness.
(yes it is technically possible to override it, but that's naughty to do so forget about it)
Only thing that comes to mind is zipping in an empty/silent wav into the map with the same name of the sound.
The reason I say you don't do it is because when you override default content with a file packed in of the same name it stays cached and persists into every other map the player plays until they restart the client.