This is exceptionally odd.

- Jemplode has no trouble upgrading the player with v300 via FTP.

- The file that Jemplode auto-downloaded and successfully upgraded the player with is binary-identical to the one that I downloaded and tried to upgrade with using Logoedit. So there's nothing wrong with the file.

- It's not file size, because I've used logoedit before to upgrade the player using both smaller files as well as larger files. At least I think I have.

- I know my upgrader and cable are working because I can easily apply the V299 upgrade with logoedit.

Still investigating.