I find sounds which are muffled or distant much more disturbing than louder, clearer ones very often, though I can also have a very exaggerated startle reflex too sometimes when a sudden noise breaks through my little "bubble" when I'm very engrossed in something.
Voices are the worst for me; for example, being able to hear the neighbours or TV characters talking through the walls of the house. When I go for counselling, the session will often be disrupted several times by people stopping to talk in the corridor outside the consultation room - I just completely lose the thread of what I'm thinking and find it very hard to pick up where I left off.
I also find it very hard to sleep in a room where there is anyone else, as the sound of their breathing really sets me on edge, even if they don't snore.
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