I've spent about an hour making this little mod for the Grunt voices adding a touch of whimsy to the game, it replaces all the vocalizations of the Grunt with responses from the Heavy from Team Fortress 2.
You can download the file from
here, you just need to extract the 'sounds' folder to the root of your Amnesia folder (I.E 'X:/Program Files/Steam/Steamapps/common/amnesia the dark descent' I'm unsure about the directory for retail users so you may need to find out for yourselves
)
It also includes the original sounds if you want to change back (they're mostly so retail users don't have to re-install just to get the old sounds again).
I would upload a video showcasing the new sounds but I feel that it'd ruin the fun!
Thanks, and have fun!