Sound Card Problem

1. Check your sound card if it is set up properly. Check to make sure your computer has a sound card, or sound processor, and it's working properly. Do one of the following:
a) If you're running Windows 7 or Windows Vista, click the Start button , click Control Panel, click System and Security, and then, under System, click Device Manager.  If you're prompted for an administrator password or confirmation, type the password or provide confirmation.
b) If you're running Windows XP, click Start, click Control Panel, double-click System, click the Hardware tab, and then click Device Manager.  If you're prompted for an administrator password or confirmation, type the password or provide confirmation.
2. Double-click Sound, video and game controllers to expand that category. If a sound card is listed, you have one installed. If no sound card is listed, check the information that came with your computer to see if there's supposed to be a sound card installed. If there should be a sound card installed, you'll need to install one. If you think you have a sound card installed, but you don't see it under the Sound, video and game controllers category, expand the Other devices category and check any devices listed there.

If there's a yellow question mark next to the name of the sound card in Device Manager, there might be a problem.

Right-click the name of the sound card, and then click Properties.

Click the General tab, and then look in the Device status box to identify problems with the sound card.

If there's a problem, you might need a new driver for your sound card.

Check if the cables are connected properly

HDMI Cables:

If you're using an HDMI cable to connect your computer to an HDMI-capable monitor with speakers, you might not be able to hear sound. HDMI cables support audio signals, but not all HDMI-enabled video cards support audio. If your HDMI-enabled video card does support audio, you might also need to set the HDMI audio device as the default audio device. To check if sound is supported via HDMI, follow these steps:

Windows 7 and Windows Vista

1. Click the Start button , and then click Control Panel. In the search box, type sound, and then click Sound.
2. Click the Playback tab, and then look for an HDMI device. This appears as a speaker icon and is labeled as Speaker, followed by the name of the device.
3. If you have an HDMI device, click the device, click Set Default, and then click OK.
   Changing the audio device might require you to restart your computer.

Windows XP

1. Click Start, click Control Panel, and then click Sounds, Speech, and Audio Devices.
2. Click Sounds and Audio Devices, and then click the Audio tab.
3. In the Sound playback section, under Default device, click the drop-down list next to the device name, and then look for an HDMI audio device.
4. If you have an HDMI audio device, click the device, and then click OK.
   Changing the audio device might require you to restart your computer.

If your HDMI-enabled video card supports audio, your HDMI-capable monitor should have an audio input, but you might need to connect a separate audio cable from your computer directly to the monitor. If the monitor doesn't have speakers, you'll need to connect a separate audio cable to a different device, such as external computer speakers or your home stereo system.

Some video cards with an HDMI output require you to connect a wire from your video card to the sound device. This usually requires a small wire connection inside your computer from the video card to the sound card. Check the manual that came with your video card for instructions on how this should be done.

If you just installed a new HDMI-enabled video card, it's possible that the video card installation software set your video card as the default audio device. In this case, you'll need to set your preferred video card as the default audio device to fix the problem. See the instructions above for help setting the default audio device.

USB Audio:

If you're using a USB audio device in addition to an existing audio device, the USB audio device might not be set as the default audio device. Try these basic troubleshooting steps:

• Unplug the USB audio device, restart your audio program, and check for sound. If you hear sound, there might be issues with the USB audio driver or with Windows not using the USB audio device as the default audio device.
• Close all audio programs, unplug the USB audio device, and wait for the USB driver to be uninstalled (this should happen fairly quickly). Next, plug the USB audio device back in to the USB port, wait for the driver to reinstall, and then start the audio program and check for sound.
• Check that you have the correct audio device set as the default audio device in Windows and in the audio program. To set the USB audio device as the default, follow the steps below in "Multiple audio devices."
• Check the audio device manufacturer's website for updated drivers.