It's happen when I try to replace internal hardisk cuz it broke.I had to have everything re-loaded onto my laptop (windows 7). Now everything thing works except my speakers, or even headphones on the front plug. I have made sure everything is plugged in correctly, turned on, all the volumes are set at the highest level possible. I have updated sound driver .All my drivers say they are fine and working. And it also not working on ubuntu ( I have Windows 7 dual boot with ubuntu. And now I external sound card. I need pro to answer this question .Please help me !!!