Default to display Computer instead of audio?

Hi all,

Relative newbie to here, so be gentle with me :)

Got a 2008 Cooper, fairly low spec from what I can work out - don't ask, wifey's car, not mine..... Anyway, she likes to have the "computer" display on, showing mpg etc rather than the default audio (or is it music, can't rightly remember) as she likes to monitor her mpg. Talking about the centre dash display btw, not the drivers binnacle thing......

Question is, can the default display be set to show the computer info or does it need manually selecting at every start-up? I've had a trawl round various places and forums but can't find anything to help.

TIA,

Simon