Phone Book Capacity Question?

Thanks to some great help here I am now conected via bluetooth on a 2010 plate Skoda Superb. Yeah. However I can't load my whole phone book.

I have an Iphone 4, connected to my work exchange account. I have 2,528 entres in my phone book in outlook. When I connect to the car it says downlaoding the phone book. It stops at approx 1821 entries. However when I go inot the contacts section on the touch screen it is only showing up to letter 'H' which is well inside the 1821 entries it says it has downloaded.

If there a capacity limit on contacts?

Thanks