Hi
What kind of soundcard do you have?
What are you using for a microphone?
You could try uninstalling the sound card in Device Manager and rebooting.
Windows will install the default drivers when you reboot.
As I said I had sound issues in Windows 8.1 but not 8.
I had sound but it was distorted especially speech, and in computer games.
I'm using a Microsoft Webcam for my mike and my sound is very good.
Sometimes it works better if you just have different drivers, look and see if you can download legacy drivers for you card.
In my case the old drivers work a lot better then the new ones.
Mike