MP3 USB failure

2015 Prius C, bought used June 2020. After some months of listening to music and audio books on USB, lost ability to read files on USB stick, first tried another USB stick; same result. Thinking the USB socket had failed I looked around for replacement, however before attempting to take console out of car I noted that I also could no longer play mp3 files written to a disc. The disc player will play standard music CDs, so I think the problem is inability with the mp3 type file. Recently took car in for a software recall, mentioned this to a tech and got a blank stare. Did not want to buy a new radio unit, this must have happened before to someone else, wondering if there is a fix?

 

Not that there was ever any response to this, but I found the issue/fix. I had to replace the factory radio, for the second time, on my 2009 Tacoma due to the common problem of skipping, resetting, and turning on/off when hitting a bump in the road. I did not waste my time putting in a third factory radio, bought an aftermarket Pioneer and my USB stick would not work in it either. The fix for both, after reading a bit on the web, was to download a FAT32 format tool, reformat the USB to FAT32, copy the audio files to the USB and now it works in both vehicles. Note that exFAT and FAT32 are not the same; your windows OS will most likely only let you use exFAT and NTFS formatting on large drives, so you will need to download a tool to do it. The free HPUSBdisk program worked just fine, find it with a search.