Yes I did do a search but it seems the multiple threads suggest NTFS which my car does not recognize at all. I used to use a smaller USB microSD card reader and it was fine but couldn't hold all of my music. So I bought a low profile Sandisk (128GB) and the only options for formatting are exFAT or NTFS. Neither one works, regardless of how many files I put on. At first I thought it might just be taking a long time for the Gracenote thing to index everything, but after 10 minutes it still couldn't find the drive let alone folders. I took a smaller drive out and formatted to FAT32 and immediately it was playing files but was taking a while to index. In one thread someone mentioned that FAT32 failed on them after a short time but NTFS worked great. So I guess my question is not only what format are you running but how large of a USB drive are you using?