DD (2.3) literally jumps at any little sound. When shes playing in the garden and an airplane goes by, she runs inside.
When the fridge/cooker/alarm clock beep or make a sound, she looks startled and says "whats that noisy mummy, whats that noisy?" - repeatedly, and I have to reassure her at least a dozen times a day.
She was terrified of the sound of the bath filling after we got a new bathroom fitted, because the bath is bigger and the taps are the waterfall type, so make quite a racket, and she would run away crying and wouldnt bathe in it for days. After much cajoling and reassuring, she stands watching the bath fill and plays in it happily now.
I just went to find her because she wasnt playing in the garden as I thought she was; she was very carefully and quietly climbing the stairs ( to goto her room, Im assuming), and I said very gently "DD...", she cried out in alarm, and then burst into tears!
Otherwise, she is a very happy and bright girl. She is non-stop throughout the day, can hold a decent conversation with anyone, and needs constant stimulation to keep her engaged and interested (think paints, crayons, sandpit, pots and pans, dollies, books shes never seen before, my iphone, anything I can get my hands on...) - which if she has, is an angel to be around.
However, after this most recent little outburst, I am a little worried now, as to why she reacts like this to noise.