YouTube sound not working?

Try deleting the ~/Library/Preferences/Macromedia folder. This worked for me.

 

Here is what the ICON should look like..

 

That worked for me, Thanks!

This sound problem had been bugging me on and off (mostly on) for a week now. As soon as I deleted the Macromedia folder the sond on YouTube played. Now I'm hoping it'll be alright after restart...

 

I'm having the same problem with the sound with youtube. I'm really new at computers other than email and watching videos. How do I get to the place above to delete? I'm afraid of deleting the wrong thing. I tried looking around, but was afraid to hit the wrong key for fear of losing a big "must have" file. Please advise with step by step instructions. Any help would be appreciated.

Thank you!

 

Fix

Wow, this is annoying.

These steps worked for me.

Open "System Preferences"
Click on the "Sound" icon
Click on the middle tab which is the "Output" tab
Click on Internal Speakers
Close

After this my sound starting working again. Hope this fixes your issue.

 

Still Not Working

Having the same problem, coincidentally after the Oct "update" of Flash Player. Now suddenly YouTube audio defaults to mute and must be manually reset for each and every video played on MacBook Pro running Mountain Lion. None of the following methods fixes the problem and I'm suspecting it's yet another Google bug in YouTube.

1. Uninstalled Flash, rebooted, checked for any leftover preferences and cache files (there were none), reinstalled latest Flash Player - YouTube still defaults audio to mute. (And there is no "Macromedia" folder anywhere on my system.)
2. Updated Flash Player settings (both through System Preferences and through the online Flash app) and applied recommended fixes from multiple web sites (clear stored data, allow 3rd party content, etc) - YouTube still defaults audio to mute.
3. Opened Audio MIDI Setup (output currently at 44.1 KHz), changed to 96 KHz, changed back to 44.1 KHz - YouTube still defaults audio to mute.
4. Opened GarageBand and played a few notes on piano instrument - YouTube still defaults audio to mute.

This is not a speaker setting. All audio works fine on the system, including non-YouTube videos. I've tried both the Flash and HTML5 options and they both have the same bug - YouTube audio defaults to mute, so I'm thinking this is not a Flash issue. Hovering over the speaker icon in the video player shows it on mute. I have to click the icon, then drag the volume slider up in order to hear sound. But, the setting is not preserved. Next YouTube video has audio reset back to mute. Very damned annoying.

 

My problem isn't that YouTube defaults to "mute," but it won't play any sound at all. It won't play on Safari or Chrome, and I've already tried reinstalling flash. I'm about out of ideas here, too.

 

No sound /

Hi, I tried the system preference, adv, delete all worked for me after restart..