I just finished updating mine from 2013 to 2014. Another DIY update you might want is a new version of the Nav maps.

You will have noticed that this is a very limited sort of software update. It's a low-risk operation in that the Software Update menu gives you the option to go back to the earlier version if something goes wrong or even if you just want to.

(In my car the system can ignore files that it doesn't need or can't use.) The ignition has to be on for this all to happen. When you select 'Software Update' in iDrive, the car will check the USB drive and, if it finds an update for the car's system, it will load it. If you find a likely update, you can download it from the website, copy it to a USB flash drive (FAT or FAT32 format), and insert the flash drive in your car's USB port (the only such port in NBT-equipped cars is in the center armrest earlier cars also have on in the glove box, which I am told is the one to use for this purpose in the older-technology cars).

You can look for audio system updates using this link, and entering your VIN: There is no over-the-air update like Tesla's. That's not quite how it works in my experience.

Idrive software update