A cordless multimedia keyboard and cordless optical mouse (PC-KBC300) have been instsalled. The keyboard works fine up to now, but the mouse is giving huge problems when scrolling up/down. When the scroll wheel is used, the page jumps in a violent way and often changes pages. (I didn't think that possible). It does not matter if I scroll slow or fast, it happens all the time. I don't know if the following will help. If I leave the computer and return later, the page that was on the monitor when I left it, is still there when I return. I thank you in anticipation of a useful response.