Audio and video you play in Firefox may be subject to one or more external volume controls. The following is based on Windows 7, but probably Windows 10 is similar.

With some audio playing (silently), click the volume control button in the Windows "notification area" also known as the "system tray" and then click Mixer. This should show volume controls for all applications sending audio to the system. Is Firefox listed and, if so, does the volume slider show that Windows is receiving audio? Also check for a separate slider for the Flash plugin, if the audio is playing through Flash.

I'm attaching a couple screen shots illustrating what I mean. Can you confirm through the Mixer that Firefox and/or Flash are not muted at the system level?

I watched a video and apparently in Windows 10 you need to right-click the speaker icon in the notification area/system tray to get the Volume Mixer.

I was able to get the volume mixer window and Mozilla was on it but no sound when I used the slider. I did not have a flash player icon on the mixer. Any other solutions or suggestions? I just updated my firefox just before doing this. I'd like to continue using Firefox but with no volume i may have to use Google Chrome as my default.

jngerbs said

I was able to get the volume mixer window and Mozilla was on it but no sound when I used the slider.

Was there any green bar or dark gray bar flashing up and down showing that Firefox was sending audio to Windows?

Do either of these test pages play audible audio?

• HTML5 Video: http://www.quirksmode.org/html5/tests/video.html
• HTML5 Audio: http://hpr.dogphilosophy.net/test/

Some users have reported Firefox going mute because it was sending audio output to a no-longer-available device, such as a headset or television. I haven't experienced that myself, but they reported that after reconnecting the missing device, they then could switch the audio back to computer speakers. Not sure if that is relevant to your situation.

I did not get a green or gray pulse when I used the firefox slider on the mixer. I also tested from these test pages and did not get any audio.

Hmm, I'm not aware of any audio level control in Firefox, other than on individual players and on the tab (a speaker icon should appear on tabs that are playing audio). I don't know where there sound is going.

jscher2000 said

Hmm, I'm not aware of any audio level control in Firefox, other than on individual players and on the tab (a speaker icon should appear on tabs that are playing audio). I don't know where there sound is going.

Thanks for your help, but I guess firefox doesn't work so well with Windows 10