For me, noise is anything I don't want to hear. If I start feeling irritated, it's because I find it painful in some way. It doesn't have to be loud, but if it's loud and I don't want to hear it, then it's definitely a painful noise. Dismissive advice is something I don't want to hear, so the noise worsens. I'd rather be handed a pillow or maybe a bag of marshmallows.