AW: „ALT“ is an abbreviation for „Alternative“ and refers to a configurable function key, also see device main user manual under “Misc Setup”, where a specific button function can be assigned via the Setup menu. The device features an ALT button field in the HMI. The following direct function assignments for the “ALT” button are available: CAM/NAVI/EQ/Setup/BT-Music/BT/DISP/iPod/USB/HDMI/Android Auto(GAA)/AV-IN/FM/DAB/CarPlay/Voice/Mute/AppList/BT-SRC Mode.