Ahhhh yes makes sense.
Mine is manual so this didn't occur to me!
I was playing with my 'sport' and 'custom' modes recently and using the boost reading (which shows demand boost - thanks scanesare
) I found that the car only demands the full 2.2bar in sport mode, in custom mode with all the settings set to the highest performance, it will not go that high, only to the same 265ps as ECO mode.
The point of that was that I was trying to get the full performance but with the soundaktor turn off, but you can't do that.
I like the natural sound of the car and always found the soundaktor to sound like an old beetle or riced-up Impreza, but I guess I just have to stop listening when I press the loud pedal and enjoy it with all my other senses 
Thanks guys.
J.
It is true and very upsetting that despite the freedom to mess with settings in Custom mode, some features always remain an exclusive privilege of the Sport mode, even if you went and set everything to Sport in Custom. Launch Control is one of them, it doesn't get activated in Custom mode, and the over-boost is another.
Truth is I don't mind Sport mode so much in terms of suspension, DCC does a good job even in Sport and the CS is anyway a bit stiffer than a GTI even in Comfort so the dampening does not vary as much, but the heavier steering and the Soundaktor are more of an issue. I've coded out the Soundaktor so I only have to put up with the sport steering which is sometimes ok. Still, why you should not be able to get the full power in Custom when you set Drive to Sport is a puzzle, what's the point of offering the Sport settings in Custom mode? Personally, I've also dealt with it with remapping (all the power and then some more all of the time) so the only thing that remains "Sport mode exclusive" is the Launch Control with which I very very rarely bother.
Since you detest the Soundaktor as much as most people do, I strongly recommend If you are not into messing with settings that would justify an OBDEleven purchase, to search for someone nearby with the tool and ask them to code it out for you. It's a 2min job.
PS. Boost readings include atmospheric, it's making (requesting) 1.2bar at over-boost, but you knew that
