Anybody help with this poser?

I use both 2002 and 2004.  In 2002 when in the Southern hemisphere the headings shown both in the flight planner and on aircraft instruments are out (on runway 10 at Broome the compass shows the a/c heading as 230.  Makes nav aproblem in that the plane will get to the destination using GPS but it's a bitch to land manually 'cos the runway headings don't tally.

Thanks, but although I fly a lot, I don,t have any experience tinkering with the program other than downloading aircraft and textures.  I have several pcs, one has both 2002 and 2004, one has 2002 only and another has 2004 only,  The problem occurs in both 2002 installations but not 2004.  I realise that AFCAD is something to do with airport layout, are you saying that each afcad has to be edited/updated or is their one program that will fix all problem airports. PS one 2002 has a variation of about 130 degs W the other is about 20 deg E out. ???