The stereo on my 2006 CR-V EX has this strange "aux" thing above one of the buttons. I assumed it meant that there's an aux input jack somewhere in the car, but I looked all over my car for this aux input jack and couldn't find it anywhere, and there's no reference to it in the manual. So, if there is no aux jack, what is this mysterious "aux" reference on my stereo? Does anybody know?