Rekordbox freezes whenever I try to export playlist to USB

 Rekordbox 5 was working fine until today. I plugged my USB in to add some new tracks to it earlier today, which I updated and DJed with only 5 days ago with no problems. The USB was not recognised when I plugged it in. I came home today and tried to add my playlists to a brand new USB, using sync manager for the first time. It exported 36% before Rekordbox froze and I had to force quit. I tried again and this time it got frozen at 9%. I then tried formating the USB and unlinking it from sync manager, and manually exporting each playlist, but the program froze at 1% export. I then tried again with a variety of different USBs and the program now freezes when at only 1% of export. I then tried updating to the newest version of Rekordbox and still it keeps freezing when trying to export. I cannot export anything onto any USB now without Rekordbox 5 completely freezing. Any ideas of why this is happening? I just need to export tracks to any USB at this point!