Hi Mini2'ers! Iv searched the forum for this problem but cant find exactly what i need to know

The other day i was driving down the motorway, with the aircon off. The air vents on the dash were closed, but there was a lot of wind noise coming through the vent on top of the speedo, plus some cold air (last setting on the climate control when it was on was 'Lo'). When i opened the vents on the dash there was cold air coming out of them, and the wind noise seemed to die down. Think that it was cos it was spread through more than 1 vent. I eventually got a bit hot and decided to turn the air con n anyway. There was wind noise again untill i switched on the "recirculate" setting. When i next decided to turn off the air con, the wind noise stopped coming through the vent. I am guessing that this is because the recirculate thing was on before i switched the a/c off? Now it seems that I get wind noise everynow and then with the air con off on the motorway. Its starting to annoy me

. Its definitly through the air vent! Is this just due to not having the recirculate button on all the time? Also, any ideas why that one off time there was quite a lot of cold air coming from my vents even with the aircon off?