Perhaps it only decreases the music volume by a preset non-adjustable amount when Navigation guidance is being given, so if you have music playing at a high volume it will still be difficult to hear the Navigaton guidance unless it is set to a higher value via the Guidance Volume setting within the Navigation Settings Menu? Also, doesn't it only cut the volume of the driver's side speaker when Navigation guidance is being given which again could mean high music volume would lessen the ability to hear a lowish volume Guidance setting? I believe the volume control on the centre console can be used to adjust the volume of any Traffic Announcement when it is being given, without affecting the music volume.
2016 Sport Nav 2.0 Petrol Automatic Arctic White plus options
Last edited by st3v3cx-3; 08-16-2016 at 04:10 PM.