What changes
Unit 5F: 0550 byte 7 bit 3 = 1 (welcome_sound), 0551 byte 0 bits 3 and 2 = 1 (vehicle_readiness_sound, vehicle_leaving_sound). A brand sound on start-up and the “heartbeat” when leaving.
Details
MIB3 adaptations function_configuration_audio → welcome_sound and function_configuration_sound → vehicle_readiness_sound, vehicle_leaving_sound. Byte and bit numbers come from the adaptation table of the MHI3 P4580 firmware itself (CP.VIP1 image); the table was checked against the catalogue maps for object 0559 — the station logo region and AM disable matched. Owners report it does not work on every MMI software: on 3454, 3611, 3620, 3801 both sounds, on 3691, 3695, 3843 only the welcome sound. Unit 5F is SFD-protected. The MMI restarts after writing. Roll back by writing the object backups from history.