Recording with Microstudio ( Vista)

[Stela]

I'm trying to use the Microstudio's record feature but when my karaoke song is playing the record button is inactive (gray). Why I can't record my voice and the song in the same time?
Please let me know if is a problem with my computer ( I have a laptop with Vista) or I shoud set up something? I've read the manual but all the settings seems to be for XP. I can't find in manual how to set up the mic or the Microstudio for recording in Vista.
Please help,
Stela