Just yesterday I noticed a strange thing my phone does when I send or recieve a text message when the messaging app is open. It makes the regular short tone (ascending for sending and descending for recieving), but then for about 3 or 4 seconds it makes the sound of a spring "boing" or a spring doorstop being snapped. This noise is ascending or descending according to sending/recieving. It doesn't make that noise with anything else, and it doesn't happen when the phone is on silent. What do you think this is? Ill try to post a video later today or tomorrow.