2004 C5 estateVTR 80,000 mls.Minor problem but annoying nevertheless.Display window on dashboard computer stuck on "check control",no amount of presses on stalk button will change it.If either button beside display window is pressed screen goes to date, temp etc but changes back to "check control" after about five seconds.Started playing up about one month ago when it needed two or three presses on stalk button to change but all windows came up in order as usual. Got progressively worse,now stuck as above.Any ideas? Fixable? I know it's a minor thing but if a car's got gizmos I like them to work! Love the C5,comfortable,great to drive,loads of space.Many thanks in advance for any information. All the best.