What happened? Did you get a sound icon on your slide? If so, did you try to click on the icon in Slide Show View? If you did that and didn't get any sound, can you get sound in other applications on your computer? If you can get sound in other applications, can you record your voice in other applications? Can you get sounds that you don't record in PowerPoint? The problem could be that your sound is turned down, that your microphone isn't configured properly, or that you are doing something wrong in PowerPoint. Give us more information, and someone might be able to help you figure out what is wrong
--Davi