Multiple output using hi fi speakers and studio monitors???

Hello,

I just purchased a Samson C-control to work as a switcher between my hi-fi speakers [connected to my amplifier] and my studio monitors. I've got everything set up right...or so I think...but, am not getting any sound out of the hi-fi speakers. The meters on the C-control are lighting up but there is no sound coming from the hi-fi speakers...which leads me to believe that the problem lies with my setup within my Mac. There is sound coming out of the studio monitors though when I activate their switch on the C-control.

Please help.

Thanks.