Missing audio coming from the computer is the most common sign of a high-definition audio bus problem. The Peripheral Component Interconnect (PCI), an input/output bus, is a system device used to connect network cards and other peripheral controllers inside the computer. In some cases the drivers for some of the PCI device components were not automatically installed, mainly, the Microsoft UAA bus driver for high-definition audio. This problem can be fixed by downloading the right driver package and installing it on your computer.
Click the link "HP: Modem Driver Installer for Microsoft Windows XP (32-bit)" listed in Resources if you run the Windows XP operating system on an HP computer; for Windows installed on a Toshiba computer, go to Step 3. For all other types of computers running Windows, go to Step 4.
Click "Download" from the HP website and click "Run" to install the high-definition audio (HDA) modem driver package. If the modem device does not work properly after the driver has been installed on your Windows XP computer, go to Step 9.
Click the link "Toshiba Audio Drivers" if you run Windows and use a Toshiba computer. Find your operating system, click the appropriate driver listed and then read the installation instructions on the screen to download the driver. If the modem device does not work properly after the driver has been installed, go to Step 9.
Click the "Start" button and click "Control Panel."
Click "System and Security" and click "Device Manager" under "System."
Click "System Devices" and right-click the "Microsoft UAA Bus Driver for High Definition Audio" device.
Click "Update Driver."
Update the "PCI" description drivers (PCI bus and PCI device) and any modem device that displays an exclamation point to the left of it. If the modem device does not work properly after the driver has been updated, go to the next step.
Visit the computer hardware or operating system manufacturer's website for further support.
Visit your computer hardware manufacturer and register to receive email notifications about your model computer. By doing so, you will increase the life of your computer when important firmware updates become available.