automatic air recirculation

this is nothing to worry, all my previous cars, Mitsu > Merc > Toyota > VW > BMW > Audi, they all the same.

Anyone gets a burn smell inside cabin when overboost? high accelerate.. (Even when Aircirculation On)

Sitting in my friend's car, I find that the smell from outside intruding into the cabin to be very obvious especially if accompanied by intrusive exterior noise.

I've had this checked and complained of excessive exterior noise and after they claimed to have realigned the doors, the cabin is more serene and no longer smelly.  The other time where it smells is when I overboost and a whiff of burnt plastics or rubber gets in.  I guess this is a by product of hard driving and nothing to be worry of.

As for the former, I've suggested for my friend to complain of the excessive noise when he sends in for his next service.  You can try this and see if it works for you.

I have the same question myself. I actually prefer recirculation so I simply leave the air recirculation button on (i.e. recirculation indicator lit).

In the owner's manual(page 79) : the sensitivity of the automatic air circulation can be varied from off to max.
what should i do, to off or max the sensitivity ,if I prefer to recirculate the cabin air (not taking in outside air)?
I have tried both , but on and off can smell the air from outside. Perhaps it will automatically taking in outside air from time to time. Any comment?