No Audio Output Device is Installed error in Vista

I clean installed VISTA RC 2 Built 5744. It does not play sound on in-built speaker and gives me "No Audio Output Device is Installed." message when you hover your mouse over the audio volume icon in system tray. When i right click on it and check Playback devices, it shows: "Speaker High Definition Audio Device Not plugged in" And its grayed out. But when i plug in my speakers or earphones, the sound works. I have tried installing new drivers from windows update. I am using the on-board audio device Please suggest a solution!

Is your audio device detected in the device manager? Have you installed the correct drivers? If your drivers are out dated download the latest drivers from the audio manufacturer's bebsite or your motherboard's website. This will help you out...!
All the best!

Also view the below tread. might help you out...!
http://forums.techarena.in/operating...ms/1124793.htm
Also specify your motherboard or sound device. Post maximum details to get a solution quickly!
All the best!