This repetition of “but soft” is funny – because he’s definitely the only one talking.
So he tells himself to be quiet and then tells himself to be quiet again?
It could be that the first one is to quiet himself – and then when Horatio or the gravedigger look like they’ve about to ask why he tells them to hush up.
Certainly it could be said twice just for emphasis, just for rhythm. But there could also be business!
