MacBook pro - no sound with Youtube videos

Hello and welcome to Apple Support Communities, gailfrombloomingdale.

If I understand your post correctly, you are not able to hear sound from YouTube on your MacBook Pro. I'd like to help.

First, try they steps in these guides:

If Safari doesn't load a page or webpage items are missing

If you can’t hear sound from your Mac speakers

If you still have no sound on the webpage, let's do some testing to narrow down the issue.

Safe mode will tell us if the issue is related to a startup item or plugins, and sometimes corrects the issue. This article will tell you how: Use safe mode to isolate issues with your Mac

If everything is working correctly in safe mode, but is not working when you get back to your user account, please check the section titled "If an issue doesn't happen in safe mode" for the next troubleshooting steps.

If the issue continues while in safe mode, a test user will let us know if the issue is isolated to your account, or system wide: How to test an issue in another user account on your Mac. If the issue happens in the test user also, then please check the section titled "If an issue happens in more than one user account."

If the issue continues, let us know the results of each of these tests. 

Thanks for using the Apple Support Communities. Take care.

If it works in the Safe Mode, try running this program when booted normally and then copy and paste the output in a reply. The program was created by Etresoft, a frequent contributor. Please use copy and paste as screen shots can be hard to read. Click “Share Report” button in the toolbar, select “Copy to Clipboard” and then paste into a reply. This will show what is running on your computer. No personal information is shown. If the log won’t post, try posting it in Pastebin and provide a link in a reply. After pasting the report in a PasteBin page, go to the top of the page, and copy the address in the URL bar. Paste that in a new reply. Pastebin. https://pastebin.com/

Etrecheck – System Information. https://apps.apple.com/app/etrecheck/id1423715984?ls=1&mt=12

Web site version if required. https://etrecheck.com