Cool idea! The amount of 'noise' I made felt pretty abstract, maybe a meter of some kind to show how close the baby is to waking up would give the player some feedback on how they're doing.
We tried to make some feedback with 4 different faces of the baby on the hud. Maybe it's not enough. In addition we had another graphic like an alert for when you are up to lose, we ran out of time and we couldn't add it. Thanks a lot for having played the game and for your comment!