I suspect therefore that you accidentally uploaded a new file as a revision of a previously uploaded asset (using the Edit tab for the asset), rather than adding it as a new asset. This has the effect of putting a new file at an existing asset's URL, which sounds like what has happened.

So if you look at those four files, you'll see that under the Publishing tab for the last one, there are two revisions of this file, each which is a different piece of music.

You can use the Publishing tab to republish the previous version of this file (and so the file and URL will match), and then re-add "killing me softly" as a new asset.

I hope this helps

Joe - Voice Admin