so when i shake my phone to say undo what i just wrote, that pop up comes tap to undo blah blah. but recently i have noticed now when i shake it, something is ratteling, sounds like the volume up and down buttons are loose!!! How does this happen from shakingg!!!!! my screen how ever did crack in the heat 2 weeks ago, got the screen replaced, could be the tech who replaced the screen? made the connection loose or something?? HELP!!!!