1. Click "Start", click "Run", input "mmsys.cpl" (without quotation marks), and then press "Enter".
2. Put a check mark next to "Place volume icon in the taskbar", and click "OK".
3. Click "Advanced" under Device volume and put check marks to the "mute" option of "Line In" and "Microphone".
4. Set Master Volume and Wave to a proper position.
5. Quit the setting.
6. Click "Speaker Volume" and set it to a proper position.
7. Click "Advanced" under "Speaker settings" and choose the proper Speakers.
8. Click the "Performance" tab and set the Hardware acceleration to "None".

Save all settings and restart your computer to test this issue.