What the bloody hell is going on with this sat nav?

Any help would be greatly appreciated! Our lovely 09 RR Sport is fab - bought last November, except for the sat nav! I don't know if it has been set up incorrectly, or we are just crap at using it, but whenever we put in an address or postcode, it seems to want to send us the most bizarre routes possible. Example - husband currently driving to mid-Wales from Swindon - it wanted him to leave the M4 and go via Stroud (completely different route from that of Tom Tom or Autoroute, which both came up with the same (sensible) route). This is a regular occurrence - we can't trust it when driving and usually end up taking the Tom Tom with us. Have tried resetting back to factory settings, but doesn't seem to work. Any advice???

Does it have a setting for navigating the route?

ie

Economic
Shortest
Fastest

That normally accounts for oddball routes.

Another one to look out for is the 'Scenic' or Places of Interest' (POI) option, I know someone who recently went to London from Cardiff, not a problem, unitl they got into London and then it took them on a tour of all the sights........

Yes - I'm pretty sure it set to us the fastest, which with Tom Tom usually takes us via motorways and A roads, however, I'll check if it is defaulting to shortest route, which would probably make more sense as it keeps trying to take us cross country. I'll have a look when he gets back - thanks!

Brilliant! Thanks guys!