I have installed Windows -8 64 bit about a month ago. Yesterday it shows an unusual behavior. Some time sound come from laptop speaker only after connecting headphone and some time sound comes from both speaker and headphone. I mess up completely as Headphone don't get display on playback devices. When checking from Ubuntu 12.04, headphone and speaker both function normally. I think solution of problem I faced is just opposite as given here but didn't work.
System configuration:- Acer Aspire 4750G, Ram - 4 GB