One of mine is really startled by every bang, the other is startled at first then gets used to it and goes back to doing her own thing. Mine are living indoors, but there are a lot of open spaces around here and several really loud organised displays. I usually leave them in their indoor run most of the time unless I'm away overnight or cleaning the run, in which case they go into the cage. This week, once it gets dark and they've had their dusk-time crazies, I've been putting them into the cage, with tons of hay, including hay stuffed into cardboard tunnels, so they can burrow in and nest, feeling snug, secure and contained. It seems to work. In the run, my biggest girl jumps and runs from hidey to hidey in a mad scramble with every bang. She's far more settled snugged into a tunnel and surrounded with warm hay.