To reinstall the sound driver, please refer to the following procedure:
1. Start up the computer.
2. Insert the Sony Product Recovery CD-ROM Disk Vol. 2 into the CD-ROM drive.
3. Double-click My Computer and double-click the CD-ROM drive
4. Double-click VAIO-Drivers-Audio.
5. Double-click Setup.exe.
6. Follow the on-scrren instruction to install the sound driver.
7. After the completion of the installation, remove the Recovery CD-ROM from the drive and restart the computer.