Audio Driver Problem

Hello,

A few months ago I was able to install the Realtake AC'97 audio driver in my PC.It was installed successfully and was working properly but I had no speakers or headphone.But
very recently I face a problem that in spite of installing this driver in my PC there is no sound in my headphone.It is should be said that realtake Sound manager cannot be installed though AV rack installed properly.....What is this please tall me!!!!!