My uncle just bought a new Acer E-380 Desktop. It came with Windows Vista pre-installed. Along with the system there are two speakers provided by Acer. My uncle works for sometime he left the system turned on. So the system goes to sleep mode on its own. But after wake up there is no sound. It only appears after restarting the system. It is a new system and this looks some kind of problem. I checked the system. After getting out from sleep mode the realtek device disappears. Is this a hardware fault.