I have a HP envy x2 pc and after a windows update I noticed that there was no sound, so to test my theroy I tried playing a video on youtube and to my surprise I couldn't hear anything so I went to go check if maybe it was because the volume was all the way down so what I went to the volume icon and it said no audio output device is installed and so I tried plugging in some headphones and it still didnt work!!! Someone please help!!!