I’ve been having the same problem with my iPhone on this site. The problem isn’t so much that the ad banner appears, as such; it’s that it then adheres to the screen at that point and scrolls up and down with it, leaving the vacuum it has left to be refilled by the same ad. The more you scroll, the more copies of the ad end up entering the screen at that point and wallpapering it. Is this possibly a software issue, rather than the advertisers? Especially since someone has said that Android doesn’t have the same problem?