Yogi is 6 months now and he is starting to be weary of things that never use to bother him. If I see him being scared of something I slow things down and bring him gently to it so that he can see there's nothing to be afraid of. He'll usually sniff it, then put it in his mouth.
Then he's ok with it. To my way of thinking when he gets a little scared and I show him it's ok, it helps to strengthen his knowledge that I will keep him safe. I also am trying to get him out and around new things more. He really has a layed back attitude and I want to nurture that and keep it growing so that he doesn't become timid. Of course, treat rewards when he does conquer his fear of something helps too.
Can't help you with the other, but your BF may be on to something with his theory. Next time can you try just "ignoring" it and listen to see what happens. Does she escalate the noise, try a different noise, go back to sleep? I'd be curious to see what happens.