Finally I find the problem. It's seems people from Microsoft mismatched something. I hope they will fix this problem or at least explain as why  "Human Interface Device Service" randomly muted sound when type on keyboard.   Just go to service and stop Human Interface Device Service (servicename: hidserv) and everything should be OK. Except smart button on the top but who care about that. I buy 40$ keyboard Dell Kb522 which I will use as cheap keyboard for 5$. I hope Dell will investigate this problem with Microsoft HID service for Windows build 1809 
Dell Kb522 Keyboard on Windows 10 1809 mute sound when type I updated my windows 10 to build 1809. My keyboard lost smart buttons for example sound mute button not work any more. Also when I type(press on keyboard keys) sound muted/unmuted. I try to search fix from Dell support and can not find. Do not worry. After a week or two many users will update there system you will receive many complains. I did uninstall keyboard driver and then install again automatically. Did not help at all. Can you install Win 10 Pro 1809 and test this in your DELL labs to simulate this problem and provide fix. Thanks     [URL]
Dell Kb522 Keyboard on Windows 10 1809 mute sound when type