Audio output device not found

Almost from the outset, the audio on this laptop has been an issue.  Randomly it stops working....the speaker icon on the taskbar shows muted.  It will not unmute or the volume slider will not move up or down.  I've tried restarting. Going through Device Manager shows " no output device found."  There are speakers installed so what's the deal? I've tried uninstalling and updating drivers.  It will work for a time and then stop again. It's getting frustrating beyond measure to see the muted speaker on the taskbar when I haven't touched the blaming thing.