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!