I've seen similar issues posted on here, but I've never found an answer to my specific issue. I have a 64Gb flash drive with 23.4Gb of music on it. When I first used it a few week ago, it worked, but it seemed to be not playing certain songs. I noticed that some of the files were .wma format(not realizing that this was an acceptable format), so I re-ripped a bunch of my CDs to MP3 format. The bit rate for most of the files is 256kbps, while some are 128kbps . The drive is formatted as "exFAT"(the default) - which is a replacement for FAT32, and my computer allows no option to format the drive in FAT32. I found that after re-ripping my CDs, my car is no longer recognizing the flash drive when I plug it in. I can't figure out why!