Need a deaf monster(s) for a level 5 party.

So I've built this cavern called the Cave of One Thousand Screams and the gimmick is that the echoes in the cavern get amplified rather than fading out, to the point that footsteps sound like gunshots if you're not walking quietly after a few seconds. I need a deaf monster or monsters to put in it that won't be affected by the cacophonous noise. Ideally one with dark vision, since there's no light in the cave.