When using Flash, I get a separate slider in the volume mixer. (Screen shot attached.) That could be due to the "protected mode" feature -- which spawns external Flash processes -- which doesn't work for everyone.

I don't know whether you have tried disabling the protected mode feature. In the old days, you would have created or edited a file named mms.cfg. Now there is a setting in Firefox. I suggest trying this for a day to see whether it helps:

(A) In a new tab, type or paste about:config in the address bar and press Enter. Click the button promising to be careful.

(B) In the search box above the list, type or paste flash and pause while the list is filtered

(C) Double-click the dom.ipc.plugins.flash.disable-protected-mode preference to switch its value from false to true.

This might not take effect until all Flash has been unloaded for a few minutes, or you close Firefox.

Any difference?

Hi,

Thanks for the feedback, but unfortunately didn't fix the issue: I've changed the value of dom.ipc.plugins.flash.disable-protected-mode from false to true, closed and reopened Firefox after confirming it was not showing up on Task Manager and the problem persists.

Actually I don't see the Flash slide at all, even when successfully playing Flash on Google Chrome.

I just did this test using this Flash Audio Test Page: http://musicofnature.org/songsofinsects/flashtest/index.html

As you can see in the screen shots I get "feedback" when the test is running indicating that sound is being processed, on both Firefox and Chrome, but I can only hear the "Insect Chorus" in Chrome.

Hmm, the mixer shows that Firefox is sending sound to Windows, but you hear nothing. And comparing the two screenshots, "Speakers" shows nothing in your Firefox example and shows the actual volume in the Chrome example.

We've occasionally had users describe problems with the audio output device. I didn't read those threads closely, but if I recall correctly, some users said they needed to plug in headphones, or change something related to bluetooth, in order to hear audio output. There's a good chance those were Flash-related (or other plugin-related) problems.

There seems to be a device selector on the Device column; if you switch that to another device, can you see the audio "playing" on that device?

Why such issues would affect only Flash or only plugins in general is a puzzle to me; perhaps someone else (or a past thread) has the answer.

Hi,

Yep, you are correct: the mixer shows that Firefox is sending sound to Windows, but I hear nothing (speakers or headset).

My USB headphone is permanently plugged in and shows no problem with sound in any other way or with any other app, except when the sound source is Flash on Firefox.

I truly believe the problem lies within Firefox / Flash not playing well. As I mentioned any other sound source other than Flash will produce clear and crispy sound via my speakers or headset, without any issues, such as YouTube which is now utilizing HTML5 if I'm not mistaken and this radio station for example: http://www.radioswissclassic.ch/en/

However if the sound source is Flash such as this radio station I will not hear any sound within Firefox or IE (which I really don't care). But this same station will work just fine on Chrome: http://inconfidencia.mg.gov.br/

I use an application named SoundSwitch - https://soundswitch.codeplex.com/ - to toggle between my headset and my speakers quickly and it works flawlessly.

I'm attaching screen shots of my SoundSwitch and devices.

Thanks a lot.

So I decided to remove Flash all together from my Windows 7 system using these steps: https://forums.adobe.com/thread/928315 Upon rebooting I reinstalled Flash and this time IE can play the audio at this page without issues: http://musicofnature.org/songsofinsects/flashtest/index.html

However the problem persists on Firefox, no change whatsoever. This is so frustrating especially because I'm able to hear the audio from this page on both my Linux boxes using Firefox.

I've also tried Firefox in Safe Mode and I even started Firefox after moving the "extensions" profile folder to another location.

Still no FlashPlayer sound from Firefox on my USB headset or speakers.

Screen shots shows IE, Chrome and Firefox playing this test page: http://musicofnature.org/songsofinsects/flashtest/index.html

As you can see there is no audio feedback bar showing up under "speakers" for Firefox.

I don't know how the output device is initially chosen for Flash. Users have complained that when they change to a different output device, the sound from the Flash plugin continues to be sent to the previous output device, but this is the first thread I've seen where it can't be associated with any output device.

Since I don't have a little triangle under speakers in my device column, does that lead to any new information if you try to check specific devices?

Hi jscher2000,

Thanks again for your reply. Sorry but I'm not sure if I understand your request "...check specific devices". I only use the Speakers (Realtek High Definition Audio) and (3-Logitech USB Headset) and they both work for everything else, except for Flash Audio on Firefox. Not sure what else I can check.

Within my Speakers drop down menu: The Liksys CIT300 is my old Skype phone, which I rarely use since I've switched to Google Voice on Obihai device. The other two REalktek Digital Outputs were never used since I built this rig about 3 years ago.

I'm posting my about:config, where I've searched for "flash". Can you or someone using Windows 7 compare these settings so I can figure out if something does not match. I could compare with my Linux boxes, but I rather compare with another Windows 7 machine.

Thank you.

Since my feeling is the output has to be going somewhere, my thought was to go ahead and select each of those output devices on the drop-down in turn to see whether Flash is using one of the inaudible/disconnected ones.

If so, maybe there is a way to change the priority of devices somehow, or hide those other devices from Firefox. I don't know anything about how to do that, however.

Ok, I've just resolved the issue by doing something I should have done initially: Refresh / Reset Firefox.

Instructions are available here: https://support.mozilla.org/en-US/kb/refresh-firefox-reset-add-ons-and-settings

Hopefully it will still works after I reload all my add-ons.

Thanks for trying to help me.

cheers.

After you get set up again, I suggest hanging onto the Old Firefox Data folder on the desktop for a time in case you discover any essential content missing. Also, if someone has an idea about a possible bad/corrupted settings file contributing to this problem, you would have the folder for forensic analysis.

Oh yes, I'm a backup fanatic so no worries about it. I've my Firefox profile saved to my D drive and this folder is backed up automatically to two different locations (online included). However for good measure I've copied it over to my desktop before resetting Firefox and I'm keeping it for reference.

Now I will copy back the "extensions" folder I've backed up to my Firefox profile and test again. I cannot live without my 10+ extensions I use daily. I will report if there is any issues.

As for the OS backup I actually create two images of my Windows OS partition every month or so using Clonezilla and Redo Backup & Recovery, so I can easily go back and restore my OS to the state it was a couple of months back if the issue is found to be corrupted files on the Firefox installation folder or somewhere else.

This issue started about two weeks ago, so I don't think I would need to go back too far on my image if the problem returns, however I will try to avoid that as much as I can since I've to load all the MS updates, etc.

Thanks and take care.