Trip display Average Mileage display etc

[V6Leaper]

I am not sure if my average mileage/average mpg/average speed display has somehow switched to manual mode.  That is what it feels like anyhow.  When starting the engine, the display reads "auto" and zero mileage/speed/mpg are displayed as I flick through the menu.  However, when the stalk button is held for a couple of seconds or more, the message "fetching previous trip settings" or similar is shown and then the previous trip readings are there.  This is now annoying me because clearly the computer has the settings stored and can access them.  When I turn the engine off it happens all over again!  The only thing of note that I can think of to upset the computer is that I had a new battery a couple of months ago (possibly when this fault first started).

Any help would be appreciated.

Graham