Do you know what is the later one in the pictures of the two black ones at all? Many thanksthey never offered updated firmware for these devices
instead they made 4 models over the years that look the same but all carrying different firmware - you want the latest as it'll be more compatible and more consistent in the way if behaves with later devices
the world of Bluetooth was turned on its head in 2012 - where the world shifted some security features, the way phone-books behave, but the main idea was to make the phone always on so you look for the car after 2012, not use the car to look for the phone (the car already knows the device is there) - its took most manufactures three iterations of firmware updates to land the shift in 2012 so everything worked the way they intended - most had it right by Sept 2012
other things happened in 2018 for motorbike headset linking up to the dashboards on modern bikes - that the issue nothing is static