The reason they remove these "easily loosable" pieces is because there's an order to put the board back together or the 3DS won't turn on. This is for replacing the motherboard, which most of the time you will buy and it won't come with the microphone, volume or IR board. Use your head kiddo. If it's so easy to loose these pieces, you should keep better track of them. We might as well just not take out any screws as well because those are very easy to loose