It could possibly be a problem with your local machine, for example a problem with the local hard disk on a sector that the "bad" file is sitting on. Have you checked that?

Also, it might be something in the file's tag data. You might want to compare the tag data between the "good" and the "bad" files. There was once a known bug where extra-long ID3V2 comment fields would screw up emplode.

Another possibility is the file name or path name might contain illegal characters.