Right just to update this properly and for future reference for any other Delta/Bravo owners out there... So the complaint is that when I start the car I get a loud clicking sound coming from behind the centre of the dashboard. It does it several times and then stops unless you change the settings on the aircon or open a window for example. So to explain what's going on then... Basically the climate control system does a self test when you first start the car, which includes opening and closing the recirculation flap which is located behind the dash at the top of the bulkhead. This flap in essence allows air from outside to circulate when open or closes to recirculate just the air already inside the cabin. The motor uses plastic cogs to do this and over time they strip their teeth off, and the motor can no longer open or close this flap. Now when I start the car and the climate control does a self test it tries to open and close the flap several times and when it fails it stops. When you press the recirculation button or open a window for example the system also tries again. The problem lies in how to fix it! It's basically a dash out job, which in itself is a horrible job taking several hours and then a replacement recirculation unit fitted, and then whole lot put back in again! Neither myself or my Tech liked the idea of this as obviously there's a lot of labour cost involved due to the man hours to do this, plus you have to ask yourself the question is it really worth it given the function this part plays? We ended up just disconnecting the flap rods from the cogs and wedging the flap in the open position to stop any further annoying clicking sound and job done!