I have connected a 256GB USB drive with quite a lot of files (~40K files and about 150GB in total size), formatted as exFAT (with MBR partitions). The first time COMAND recognised it and started reading metadata from it (though it only listed 10K files), however playback from track to track was very laggy; it would easily need 5 seconds to move to the next track.

Now it does nothing, apart from a message stating that "Reading USB device...". I've left it a couple of hours and it's not changing. I've formatted and renamed the drive, even put the files into a Music folder; still nothing; I can't make COMAND treat this as a new USB drive and try to read all the files again. The drive is readable from my PC..

At some point, I removed the flash drive from USB 1 and attached it to USB 2. The first time I did that, the "reading" message didn't go away and it didn't seem to recognise that I reattached the device. The next day I did the same and whilst it DID recognise that I removed the USB drive, it did not when I attached it back. I tried to reset it from the system menu but it didn't help (although I restored the backup I took right before the reset, so I don't know if some kind of a music database was exported as well).


Any ideas about what could be wrong? Is it the number of files? Is it the flash drive? Is my COMAND toast? Is there a reset approach that would work? Thanks!

So, to answer my own question, COMAND has other issues with media. It won't play from CD or Bluetooth either (but usually it will if I go to the car the next day), and when choosing the speakers as the audio output for the rear screens, there is be no sound coming.

Guess it's time for a warranty claim, disappointing considering how I pamper the car and with less than 3 months of ownership. I now wonder if there are other subsystems waiting to fail and I am a bit concerned since I've arranged a few weeks' worth of vacations and am going with the car.

I thought I'd update this just for closure. I took it to the dealer and they fixed it. They told me it was the software that got corrupted, so they updated it and solved the issues.
Dealing with software is my day job and I cannot fathom how could that possibly be true. It's very uncommon for software to just get corrupted and start exhibiting erratic behaviour without a hardware reason, so I don't know. Usually if software "gets corrupted" it leads to crashes but even that tends to be caused by hardware reasons (e.g. bitrot, bad sectors on a drive etc).

I didn't lose many settings which is weird, since a reset usually... resets everything, including the settings. I did however notice that the volume changing pop-up became gray compared to blue that it was before. I am not sure what to make of this and if it means that there was a version upgrade/downgrade.