norwegianskodaguy

I don't want to answer for OP here, but in my case, it is not depending on wether the ac is on or off. When the noise comes, I have tried to turn all the way to low temp, up to high temp, turned on the recycle air button, change fan mode, but the sound remains the same.

I have the same problem on my 2010 fabia. Sound comes on in cold weather, doesnt matter if the ac is on or off, goes away after some time (sometimes not) gets louder when breaking or changing gears. Hpoe you guys can find a solution..