Karaoke previews but won't play

I have a new WIN7 machine that i installed Gameex on. My old XP runs karaoke fine on it. I've got the two side by side but the Win7 will preview the lyrics and music but once i select a file it goes black for a few seconds then jumps back to the list. I tried downloading the new shark codec like i've read in the forum. I reinstalled gameex and directx twice but still no good. i've searched the forum but haven't found a definative answer. Any ideas?