The “button” with BAND on it is what is used in the US market…AM/FM/Satellite.
In Europe and perhaps some other markets…they have a button with a different icon since they have radio band options we don’t have here. Iin Europe, they have TRAFFIC INFO button beneath the MODE BUTTON (i.e. with the cars/antenna graphic), the music source (FM RADIO, DAB RADIO, USB, iPhone, Spotify, etc.) will be interrupted by traffic updates for the area you are in. The reports usually last 2-3 minutes, but on the display a message appears immediately giving you the option to cancel the current message by pressing down on the iDrive controller.