1)You can try to clear your cache and cookies in Firefox, click on the menu button in the top-right corner of the window and select "Options". In the "Privacy & Security" tab, click on the "Clear Data" button. Make sure to select the "Cookies and Site Data" and "Cached Web Content" options before clicking on the "Clear" button. 2)Check for any extensions or plugins that may be causing the issue since some extensions or plugins can interfere with the audio in your browser. To check if an extension or plugin is causing the issue, try starting Firefox in Safe Mode by holding down the "Shift" key while starting the browser. If the audio works in Safe Mode, it may be an issue with an extension or plugin. You can try disabling or removing the extensions or plugins one by one to see if that resolves the issue. 3)Restart your computer and try again If none of the above help, you can try reinstalling Firefox to see if that resolves the issue