I am using a Dell Inspiron 15R with windows 8 OS and Firefox was working alright till the version updated to 38.0.5. Now even in FB as well as U tube audio only

This sounds like an issue with hardware acceleration, either in Firefox or in Flash. Flash video playback issues can be resolved by disabling hardware acceleration in your Flash Player settings. (See [[Flash Plugin - Keep it up to date and troubleshoot problems|this article]] for more information on using the Flash plugin in Firefox). To disable hardware acceleration in Flash Player: #Go to this [http://helpx.adobe.com/flash-player/kb/video-playback-issues.html#main_Solve_video_playback_issues Adobe Flash Player Help page]. #Right-click on the Flash Player logo on that page. #Click on '''Settings''' in the context menu. The Adobe Flash Player Settings screen will open. # Click on the icon at the bottom-left of the Adobe Flash Player Settings window to open the Display panel. <br/> <br/>[[Image:fpSettings1.PNG]] <br/> # Remove the check mark from '''Enable hardware acceleration'''. # Click '''Close''' to close the Adobe Flash Player Settings Window. # Restart Firefox. This [http://www.adobe.com/support/documentation/en/flashplayer/help/help01.html Flash Player Help - Display Settings page] has more information on Flash Player hardware acceleration, if you're interested. Does this solve the problem? Let us know.