Connecting Stackmat to my laptop

[KyLilyCuber]

Hey guys, im having some technical difficulties right now. I have just received a 3.5mm to 2.5mm male cable from Deal xtreme. My timer is a stackmat pro timer. Okay so, i connected the 2.5mm jack to my timer, and the 3.5mm jack to the mircophone input on my laptop. Im using prisma timer by the way, so yea i changed the timer trigger to stackmat timer and the stackmqt timer input device to my laptop's microphone. And a red bar on the top of the screen pops out: Error:Couldn't select stackmat timer. Please use space key.

so guys, i would like to know how i can solve this problem.

Thanks in advance