Speedlink Medusa 5.1 setup?

[GSDog]

I'm trying to setup my old Speedlink Medusa 5.1 headset that I haven't used for years. It's the one that comes with an amp.
I don't know where the green, blue and red cables are meant to go on the amp and my Audigy 2 ZS soundcard. So far I can only get sound to come out the centre but the front and rear doesn't work. I have it set to 5.1 in the sound settings in Vista so I think I probably have the wires plugged in incorrectly.

Does anyone know where the wires are meant to go?

 

[Alexrose1uk]

Green is meant to be front, red is often center/mic, and blue is often lineout/surrounds.

 

[strumpusplunket]

I have the Audigy 4 and the same headphones.

The front connector on the amp connects to line out jack 1 on the card; rear connects to line out jack 2; and sub/cen connects to line out jack 3.

On my Audigy 4, jack 1 is green, jack 2 is black and jack3 is orange, and they run from right to left in order as you look at the back of the machine.