From the top tool bar, select:
• Check the box: "enable voice chat"
• Select appropriate input and output devices from the respective drop down menus
• From the left hand side menu (General is top selection) pick: "Audio & Video"
• At the bottom select the 128 kbps radio button if you have a reliable broadband Internet connection
try a lower setting, especially if you have connectivity problems in SL
• Adjust "Volume: Master" slider to the middle (I have the remainder of my volume sliders set at maximum)
• Close menu
• Located at bottom right of the main screen you should see a "TALK" button, directly to the left is a button that appears to have talking balloons (like in a comic strip) click the balloon button
• A small window, which is labeled "Active Speakers," should appear on the left-hand-side of the screen - lower the volume slider to the middle
• If you have another speaker icon and slider on the right side of your main screen make the same adjustment. You can adjust each of the volume settings at anytime. However, the default setting just about blew out my speakers and my ear drums!
Note: If you still have audio problems, try adjusting your audio settings in your control panel -
[Start--Control Panel -- Sounds and Audio Devices - click tabs to adjust settings].