I am using Windows 7 Ultimate 32 bit. Previously I used Windows XP SP2. In that my head phones worked fine. I used a PC headset with microphone & volume control. Now in windows 7, head phone is not working. When I connected the head phone and checked the playback devices it doesn't shows the head phone. what can i do to make the head phone work.???? I am using Realtek High Definition Audio Driver version 22.214.171.12464.