HP Envy Laptop Sound Suddenly Stopped Working

I was working on my computer this afternoon (Windows 10 o/s) and my computer went blank and restarted on it own. After the restart, my sound no longer works on either my speakers or headphones. Made sure it wasn't muted, checked sound in control panel, checked services to make sure Windows audio was running (stopped and restarted), restarted the computer. None of these things are making any difference. Someone please help!!!