C5 blows cold

[Dohnut]

I have a C5 new shape 2.0 VTR.
Wonder if anyone has the same problem, put the heater on auto and drive 65 mph plus, and I get a cold draft blowing between the steering column and the panel above the pedals, hot air is passed through the foot vents and the side and window vents, just this very cold air cutting across my knees.

It feels like Air-con air, blowing through as the metal around that area is very cold, however put the air to recycle or move the controls to blow down or to the vents then the cold draft stops straight away.

First thought was that there was a steering gaiter adrift, or that a flap was not strong enough to stay shut at high speed.

Needless to say I have had the car back to the dealership and, yes you guessed it they say they can find nothing wrong. Any help or anyone with the same problem, would be grateful.

As I said it only happens in the auto mode and at high speed, very bad at 80 to 90, yes I know, but like the policeman on the M54 I too have to familarize myself with the handling of the car.