It's your PC settings Frank. Try clicking on the link below and turn you volume up.
https://www.youtube.com/watch?v=Ec8xNfJV-SM
Reasons That YouTube Videos Won't Play
Most of the issues that can prevent YouTube videos from playing can be broken down into these basic categories:
Browser problems: When YouTube videos won't play, it's usually a browser problem. Refreshing the page fixes the problem a lot of the time, but you may need to update your browser or
clear the cache.
Computer problems: Most computer problems that prevent YouTube from working require a simple restart. You may need to update your computer at the same time.
Internet problems: Local networking problems can usually be fixed by unplugging your modem and router and then plugging them back in. If your internet connection is especially slow, lowering the YouTube video quality will also help.
I would suspect you have a browser issue. If using Microsoft Edge or Explorer, consider changing browsers to Chrome or Firefox of something else.