Check the Volume Mixer

1. Open Firefox and play content that should play sound, such as this Firefox video.
2. ClickRight-click the volume icon in the Windows taskbar.
3. Click MixerOpen Volume Mixer. The Volume Mixer window will appear.
4. Make sure the slider for Mozilla Firefox is not muted or at the bottom.

Check your audio device

Make sure that the audio device (such as speakers or headphones) are turned on and connected to the computer properly.

Other solutions

Check out whether other applications on your computer can play sounds. If they can't:

• Follow Microsoft's Fix sound problems tutorial.

If Firefox is the only application that you can't hear sound in:

• Try the solutions in Fix common audio and video issues.

Make sure other applications on your computer can play sounds. If Firefox is the only application that you can't hear sounds in:

• Try the solutions in Fix common audio and video issues.

If no application can play sounds:

• See Apple's Troubleshooting issues with no audio from built-in speakers on Macs.
• If you have an external audio device, check whether it's turned on and connected properly.

Make sure other applications on your computer can play sounds. If Firefox is the only application that doesn't play sounds:

• Try the solutions in Fix common audio and video issues.

If you can't hear sounds in any other applications:

• Make sure that the audio device (such as speakers or headphones) are turned on and connected to the computer properly.