Addresses microphone and speaker-related issues with Yahoo! Messenger. Some of the issues may include:

• Voice Call
• Video Call
• Voice Conference
• Unable to hear or poor sound quality with Alerts and RingTones

You may receive the following error messages:

• "This computer does not support the required uncompressed audio format."
• "The computer does not appear to have audio input capability, or it is not configured correctly."
• "Not authorized to join the conference"

Missing audio compression codec in Windows systems.

To troubleshoot your issue with audio, please follow the steps for each procedure and then check to see whether the issue has been resolved.

Download and install the following software updates:

1. Install the latest version of Yahoo! Messenger.
   Note: Both you and your contact should be using the latest version of Yahoo! Messenger for Windows to ensure full compatibility.
2. Microsoft Windows Update
3. AC3 Filter - This is an audio codec.
4. DirectX Runtime Web Installer

Check with the Video and Voice Setup Assistant:

• Run the Video and Voice Setup Assistant to test your microphone and speakers.

Check your system volume:

1. Double-click the Speaker icon in the Notification Area of your Windows Taskbar at the bottom-right corner of your screen.
2. Uncheck the Mute all checkbox if it is selected.
3. Make sure that none of the options have been set to mute and that all levels are set above 50%.
4. Click and drag the Master Volume slider bar to the top.

Check your audio hardware:

Use the following links on your PC to determine whether your audio hardware is working properly without Yahoo! Messenger.

• Windows XP
• Windows Vista, 7, and 8.

If the issue continues, please see the help article about troubleshooting steps for Yahoo! Messenger.