Continuous Beep - Freelander 2001
 

Hi guys.
Our freelander has started to beep while driving. About 1 week ago, it would beep once, about 30 seconds from start up. No warning lights come on at all and the car seems to be running well.
As of yesterday, the car has started beeping continuously in 20 second intervals. Again, no warning lights are shown.
It is a 2001 soft-back model, manual transmission, 1.8 petrol engine with about 72000km on the clock. Cam-belt changed recently.
I would appreciate any help or direction on this issue please.
Thanks in advance.
Col