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Mono audio

  • 2 replies
  • 1 has this problem
  • 14 views
  • Last reply by cor-el

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Whenever I play a video file (on FB or YT), the audio only plays on the left side. If the video has stereo audio, all is fine, it is only when the original video only has mono audio. I have checked to make sure the video didn't just have audio on the left side only by playing the same video on YT in Safari, the mono audio played through both channels. It would appear that Firefox, upon seeing audio that is only mono, send its out to my audio interface on the left side. This just started a few days ago. Not sure if it is a bug with the latest FF (61.0.1) or something got set improperly. I cannot find any settings that would affect this.

I am on an iMac Retina, Sierra OS and using a UAD Apollo interface.

Whenever I play a video file (on FB or YT), the audio only plays on the left side. If the video has stereo audio, all is fine, it is only when the original video only has mono audio. I have checked to make sure the video didn't just have audio on the left side only by playing the same video on YT in Safari, the mono audio played through both channels. It would appear that Firefox, upon seeing audio that is only mono, send its out to my audio interface on the left side. This just started a few days ago. Not sure if it is a bug with the latest FF (61.0.1) or something got set improperly. I cannot find any settings that would affect this. I am on an iMac Retina, Sierra OS and using a UAD Apollo interface.

All Replies (2)

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Security Issue, please update your Flash 21.0 r0 by removing it with this tool : https://helpx.adobe.com/flash-player/kb/uninstall-flash-player-mac-os.html Reinstall with Flash Player Version: 30.0.0.134 Current Version https://get.adobe.com/flashplayer/otherversions/ Step 1: Select Operating System Step 2: Select A Version (Firefox, . . . .) Note: Other software is offered in the download. <Windows Only>

As we do not know what you are listening to HTML5 or Flash please do the above.

We do not know your security software, what is it please ?

Nor what Extensions ou are using :

Try Firefox Safe Mode to TEST & see if the problem goes away. Firefox Safe Mode is a troubleshooting mode that temporarily turns off hardware acceleration, resets some settings, and disables add-ons (extensions and themes).

If Firefox is open, you can restart in Firefox Safe Mode from the Help menu:

  • Click the menu button New Fx Menu, click Help Help-29 and select Restart with Add-ons Disabled.

If Firefox is not running, you can start Firefox in Safe Mode as follows:

  • On Windows: Hold the Shift key when you open the Firefox desktop or Start menu shortcut.
  • On Mac: Hold the option key while starting Firefox.
  • On Linux: Quit Firefox, go to your Terminal and run firefox -safe-mode
    (you may need to specify the Firefox installation path e.g. /usr/lib/firefox)

When the Firefox Safe Mode window appears, select "Start in Safe Mode".

SafeMode-Fx35

If the issue is not present in Firefox Safe Mode, your problem is probably caused by an extension, theme, or hardware acceleration. Please follow the steps in the Troubleshoot extensions, themes and hardware acceleration issues to solve common Firefox problems article to find the cause.

To exit Firefox Safe Mode, just close Firefox and wait a few seconds before opening Firefox for normal use again.

When you figure out what's causing your issues, please let us know. It might help others with the same problem.

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This can happen if you have a multi-channel sound system that doesn't report all channels properly.

You can set this pref to true on the about:config page to see if that works.

  • media.forcestereo.enabled = true

You can open the about:config page via the location/address bar. You can accept the warning and click "I accept the risk!" to continue.