Ever since I bought my zhp about a year ago there has been a rattling in the door when going over bumps if the window isn't up (maybe a broken clip holding the window) but the window was going up and down fine until recently so I ignored it. In the last month or so my auto down has stopped working, at first I had to press the button really hard and hold for a second to get it to work but now it won't go down automatically. It will still go up. Is it the switch or is it some sensor in the door that's bad?