How to Fix a Microphone That Is Not Working in Firefox
Practical steps to find and fix a microphone that is not working in Firefox, from site permissions and browser settings to operating-system checks.
Identify the symptom and environment
Start by noting exactly what happens in Firefox. Does a video call display a microphone blocked message, does an audio test show no input level, or does the site never ask for permission? Record the operating system and computer type, whether the microphone is built in, USB, Bluetooth, or part of a headset, and whether the problem occurs on one site or several. This helps narrow the cause before changing settings.
Isolate where the fault occurs
Separate the possible causes in this order: hardware and connection, operating-system permissions, Firefox permissions, and the input device selected by the site.
Check the hardware and connection
If the microphone is external, disconnect and reconnect it, try a different port where practical, and check any physical mute switch or inline control. For Bluetooth devices, confirm the device is connected and selected as an input device in the operating system before testing in Firefox.
Check operating-system permissions
On Windows, open Settings, then Privacy, then Microphone, and confirm microphone access is enabled and that desktop apps can use it. On macOS, open System Settings, then Privacy and Security, then Microphone, and confirm Firefox is enabled. On mobile devices, check the app permission for Firefox in the system settings. If Firefox is not listed or is disabled, change that before continuing.
Test in another app
Use a separate audio recording or calling app to see whether the microphone produces sound outside Firefox. If no app can hear the microphone, the issue is likely with the device, connection, or operating-system input selection. If another app works, continue with browser settings and site permissions.
Try reversible fixes in order
Allow microphone use for the site
Select the permission icon or site information icon in the Firefox address bar. Find the microphone permission and set it to Allow. On some versions this appears as a temporary permission that can be kept or removed after the tab closes. If the site previously blocked the microphone, change the setting and reload the page.
Choose the correct input device
Open the site's audio or device settings, if available, and select the intended microphone rather than a default or virtual device. Browser and site interfaces can remember a previously chosen input device, so a newly connected microphone may not be selected automatically.
Review browser settings and the page
In Firefox settings, open Privacy and Security and check the microphone permission list. Remove the site entry, reload the page, and accept the permission prompt again. If the prompt does not appear, confirm the page uses a secure connection and close other tabs or apps that may already be using the microphone. Restart Firefox after changing these settings.
Confirm the result
Return to the page or call that originally failed and test its intended action. Watch for the indicator that shows whether Firefox has granted microphone access. If the site includes an input level meter, speak and check that it moves. If there is no meter, make a short test recording or ask the other call participant to confirm they can hear you.
If the problem remains
Keep a note of the operating system, browser version, microphone type, and the site where the failure occurs. If the microphone works in another app but not in any Firefox site, try a new Firefox profile or check the browser's update status. If the microphone works on some sites but not one, the site's own device selection or account settings may be involved. If the microphone is not recognized by any app, contact the device or computer manufacturer's support rather than assuming the hardware is permanently damaged.