I have been using Firefox to join our web conferencing service (Callbridge) for years exactly the same way, but suddenly audio fails to work presumably since a recent Firefox update. (I'm currently running 127.0.2 (64bit) ) The mic in my headset works great in Firefox on other sites including onlinemictest.com. The mic is recognized by Firefox and permission is provided for the site. When I speak, there is an indication that my voice is heard by Firefox, but it is as if the mic is muted...no sound through Firefox even though the mic is not muted. Again, in another tab on a different site, the mic will work. If I use Microsoft Edge browser with the same setup for Callbridge, everything works fine. In Firefox it does indicate I have provided mic permission to the site, and the mic is clearly seen and working, but no sound from FF in the web conferences. I have tried saving mic permission for the site, as well as removing it from Tools...Settings...Privacy & Security...Permissions...Microphone and permitting Mic use each time the site is launched. Page Info settings are all correct with permission to use the mic and speakers and I have tried enabling autoplay for the site. I believe any Windows or hardware causes can be eliminated since the same setup works in Edge browser. It seems to be just a Firefox issue that has appeared recently when using the Callbridge site. Any assistance would be appreciated. Thank you in advance.