My 17-55 didn't creep when I bought it a year ago, but now after the year of regular use it zooms out to 55mm freely on its own anytime the lens is pointed downward. It's particularly annoying to have it extend between shots just because I'm looking at the LCD on the back of the camera.
Is there a user-accessible tension adjustment, or is this something I need to send the lens back to Canon for (every year?). I'd rather not go with the rubber band solution I had on my old 100-300, because that does interfere with normal operation.

