I think you're falling into the "dreamy" state". Any voices or whatever is because you're probably in the hypnagogic state of sleep(transitions between waking and dreaming.
You don't want to fall asleep or you're missing the meditation. You want to be wide awake while somewhat drowsy. I wrote about these issues you're talking about in another thread here. Solutions For Losing Focus And Falling Asleep>>> http://www.spiritualforums.com/vb/sh...d.php?t=130802