Quiet voices and ...

Hello! I have installed the newest Realtek sound drivers, and in "test speakers" non speaker didn't make a sound. So I experemented, plugging the cable in different colours [green or blue]. It didn't work. But it worked, when I "transformed" the blue to "Rear speaker Out" and marked in Four speaker mode. It worked nicely, but the problem was that they worked as the rear speakers. Ok,got over the problem, thought that will be ok like this. Thought that the important thing was that the sound worked. It was all good, until I started to listen a song. Everything was nice, exept the voice was very quiet. And I don't know how to make it right. Maybe someone can help me?