Is the cable a TRS or TS type?
What soundcard? I'm confused. Are you patching the speakers off the fast Track or off an internal soundcard?
Is this the Fast Track model? Post a link to the specific product you have.
M-Audio Fast Track USB | Sweetwater.com
Or is it the Ultra? On the ultra the jacks on the right side in the back are channel inserts. Use a pair of the line outputs and get a pair of TRS-TRS cables.
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