I have a 1 TB USB hard drive that I was using in my 2012 A4. With about 600 GB of music, it worked flawlessly. In my new 2018 A5 Sportback, the same drive is behaving strangely. I can see all the album directories, but MMI sees music in around a third of them. Most when accessed state they're an empty folder. Any ideas if there are any limitations on hard drives in the Sportback?

 

You are a lot farther along than me. Have been using usb drives for several years in my trucks. Can't find a usb port in my wife's 2014 q5. How do you attach a usb drive to the car?