I have an A6, 2.0T, 2017 Premium model. I use USB sticks to load music when I do long road trips. Yes, I know I can stream but my issue is with something in particular when using USB sticks.
I loaded a bunch of music some time ago in one of my USB sticks and had no problem whatsoever. Before a recent trip I loaded some additional music by ripping various CDs (all of my music is ripped form CDs). When I plugged the device into one of the USB ports in my car (the one I always use for USB sticks) I noticed the recently copied music was either not there OR the directory was there, but it was empty. I checked with a laptop to see if the music was actually there, and it was (and it played as well).
That was weird enough, but it gets weirder. I decided to delete all the music from the device and then reload all the music again. Out of curiosity I plugged the empty USB stick into the car UISB port, and it showed the same directories as before, but the USB stick is empty!
What's going on and how do I get it to erase these directories from MMI (I imagine it stored them initially somewhere on MMI and that's what it is showing me) and when I reload my USB stick to recognize these additions?
Thanks!

 

I solved the problem by reformatting the USB stick, reloading the music, BUT also resetting the sound configuration. I tried resetting the sound configuration first, but it didn't work so I then formatted the USB stick. I have no idea if it was the combination of the two or maybe just the reformatting of the USB stick. Regardless, this is not the first time this has happened. Hopefully newer models have fixed this issue.