As some of you are facing the problem where as you are able to hear only audio. Follow the below given steps to fix this issue.
Please check the following:
1) Make sure you’re using the latest version of Flash Player. To update, click the following link Adobe - Install Adobe Flash Player
2) Empty your browser cache
Depending on the browser, select the appropriate option in the menu and be sure to empty all the cache items.
3) Disable your software add-blocker
You may have an add-on to block ads that is installed on your browser. This may impact the video playback, so you should disable this module. For this, make sure you double-check your browser plugins.
4) Disable hardware acceleration of video playback
Click the right mouse button in the middle of the video or any flash animation
In the menu that appears, click the icon on the far left
Uncheck "Enable Hardware Acceleration" to disable this feature.
Refresh the page.
5) In the flash plugin settings (4), go to "global settings" then click "local storage settings" and ensure that the first box is checked (allow websites to store informations on this computer)
For most of the time - Step # 4 will do the trick. This will resolve your problem.