My laptop upgraded from Windows 7 to Windwos 10. And it worked well for a while.   But yesterday it got a new Windows 10 update and started to update the OS automatically. The update took a long time. After update, it seems okay but I found the audio function can't work.  It shows error icon on the status bar in the right-bottom corner. I click the error icon and it launched the diagnostic program. But this program can't fix it.   I checked the device manager and there is no any error for audio device. But I also downloaded driver and installed it again. It still can't fix it.   Please tell me how to fix this issue.