Problem with D700 and CF 16GB card - please help!

Hi folks,

I just got myself a 16GB Sandisk Extreme III CF card for use with my D700. It works OK for the most part. It shows that I can take 620 RAW shots from blank.

The problem is when I reach 620 the card shows that I have 15 shots left but the camera then flashes a "CHA" message on the top LCD (in the counter on the bottom right), and I get a message that I have a "card malfunction" on the rear LCD.

Switching off and on allows me access to the shots, and after deleting a few I can carry on shooting, only to get the same error message when I reach the end of the card.

Is this a problem with the card (in which case I'll return it) or this is a firmware D700 issue - where the camera is failing to detect that the card is full?

Any thoughts would be much appreciated.

Thanks,
Tahsin