Plug the empeg into your computer with the serial connection and then use hyperterm or equivalent to look at what the empeg prints out on the serial port. Read this bit of the FAQ for exact details on how to do it. You don't need the developer version of the firmware loaded however as you're more interested in the boot up messages.

It should be a lot more informative about what's wrong. Paste it into a post on here so we can have a look at it.

- Trevor