This post is just to share a possible solution on something that may become more common as this unit gets older. I am wording this in various ways so that searches on the web may reach it more easily. Feel free to add comments in ways that may help along these lines. NO real solution was found as far I could tell after several days of searching. I dumbly stumbled into this solution. It had to be by accident...I am not that bright.
Issue: The computer does not "see" the E-mu 0404 USB anymore AND
-- You have been using the E-mu 0404 USB successfully for a long while, like years.
-- Or, you bought the E-mu 0404 USB used and the problem began shortly after. It does not matter what OS (WinXP, Win7, etc.), the E-mu 0404 USB is not working.
-- The E-mu 0404 USB power light turns on but nothing else works
-- Using the USB connector in any of the PC sockets yields the same result: the E-mu 0404 USB is not detected
-- Changing the USB cable does not fix this problem with the E-mu 0404 USB
-- Attempting to change the drivers to the last ones from Creative is worse because the drivers for the E-mu 0404 USB need to detect the unit in order to install. (BTW, Try NOT to unsinstall the [previously] working drivers for now)
-- You have been using the factory original "Creative" wallwart power supply (it could be some other type/brand, for all I know)
-- You suspect that this power supply could be at fault, so you test it with a voltmeter. Bummer! You find that wallwart happily provides nominal 5 volts. So that's that...or is it?
In desperation*, I decided to test the Creative wallwart once again to make sure of the voltage. In stupidity, I switched the voltmeter to the wrong function, "current". Huh! Guess what, the current was too low. Re-tested voltage and then current again. Same thing. Good volts but low current, nowhere near the 1000mA, more like close to 0.
I first rigged some AA batteries into a quick supply and it worked great. Then I found that I had a 5v/1000mA wallwart in the spare bin and patched the old cable from the Creative wallwart (good cable with shielding) to the replacement wallwart. Like new!
BTW, if this happens to you, you may not necessarily want a "Creative" or similar switching PS replacement. For listening to music, check around the forum to get a linear PS replacement. I may still do this myself.
*After all this you feel like there is little choice. Your great E-mu 0404 USB is bricked. You can't even buy a new one. It is discontinued. A factory repair is not practical. It is either buying a used one or something else...and there really isn't "something else" THIS good for a reasonable price. In my case, I no longer use the 0404 USB for music listening. However, I keep it hooked up as a backup (in case the "other" USB DAC goes south) plus I use it often to drive the calibrated microphones used for taking measurements (phantom power for 2 mics!).
