Hi everybody!
I'm the very happy owner of a 2011 Fit. It's a great car.
However, I've been having a little trouble with the base model stereo. I am a college student with a long commute, so I frequently listen to lecture during my drive to school. The easiest way to do it is to load lecture mp3s onto a my USB (a clipit) and plug that into the USB receiver in the glovebox. It's all gravy, until a week later, when I plug the usb into my computer, delete what's on the stick, and add the newest lectures.
The car seems to store the delete tracks somehow. They don't show up when I put the USB in my computer, but when I turn on the car, it plays old stuff. In the past, I fixed this by reformatting the USB, since the USB seemed to be the source of the problem.
Then I was short on time one week, and wasn't able to transfer my mp3s onto the USB. Instead, I used a cable to plug the recorder directly into my car's USB port.
And I heard a long deleted lecture. Like 6 months ago old. It was about the last time I used this recorder/USB setup to listen to lectures in the car.
Now I am thinking that the Fit's stereo must keep some kind of data cache. I'd like to clear it out, or at least understand how it works. Does anyone have insight into how this works?

 

Without getting to crazy...

Most file systems contain an index of where the data is physically stored on the drive. When you delete a file it is removed from that index so as far as the computer accessing said file system it simply cannot see it and overwrites that part of the drive--most un-delete software exploits this principle to recover deleted files by searching beneath the file systems index.

I wonder if the fit scans the USB drive and builds its own index. Though after a format it should still be able to read the data then too. Maybe you deleted the files and they are still on the USB stick in a .trash directory? Try emptying the recycling bin and see if that affects it?