It's easy for Jouno's heightened senses to be a nuisance, and loud noises in particular are a lot worse for him. To the point he wants to chop his ears off.

It was a loud rainy night, thunderstorms roaring outside the window. Jouno sat on the top of your shared bed, an irritated expression on his face as his hands pressed down his ears, a desperate attempt to muffle out the loud noises.

This was clearly too much for him right now.