Glos Guy, I know it’s perception but I think the standard sound in the X1 is very much better than in the XC40. The bass speakers are under the seats and give a much better spread of sound than what’s behind the dashboard in the XC40. Also the XC40 has very small speakers only in the top of the rear doors, making the sound in the back very weak.
To my ears there’s a lot of digital tinkering with the XC40 sound to improve it whereas the X1 sound is more natural.