Most audio problems are a result of improper, defective, or misconnected cables; incorrect drivers; or resource conflicts. Audio problems that occur when you have made no changes to the system are usually caused by cable problems or operator error (such as accidentally turning the volume control down). Audio problems that occur when you install a new audio adapter (or when you add or reconfigure other system components) are usually caused by resource conflicts or driver problems.
To troubleshoot audio problems, always begin with the following steps:
- Shut down and restart the system. Surprisingly often, this solves the problem.
- Verify that all cables are connected, that the speakers have power and are switched on, that the volume control is set to an audible level, that you haven't muted audio in Windows, and so on.
- Determine the scope of the problem. If the problem occurs with only one program, visit the web sites for Microsoft, the software company, and the audio adapter maker to determine if there is a known problem with that program and audio adapter combination. If the problem occurs globally, continue with the following steps.
- Verify that the audio adapter is selected as the default playback device. If you have more than one audio adapter installed, verify that the default playback device is the audio adapter to which the speakers are connected.
- If your audio adapter includes a testing utility, run it to verify that all components of the audio adapter are operating properly.
- If you have another set of speakers and /or a spare audio cable, substitute them temporarily to eliminate the speakers as a possible cause. If you have a set of headphones, connect them directly to Line-out on the audio adapter to isolate the problem to the system itself. Alternatively, connect the questionable speakers to another system with a known good audio adapter, or even an MP3 player or portable CD player.
If the problem is occurring on a new system, or one in which you have just added or replaced an audio adapter, take the following steps in order:
- Verify that the speakers are connected to the correct jacks. Connecting speakers to the wrong jacks is one of the most common causes of sound problems. We do it ourselves from time to time.
- Check the troubleshooting sections of the Microsoft web site and the web sites for your motherboard and audio adapter manufacturer. Some audio adapters, for example, have problems with motherboards with certain Via chipsets, while other audio adapters have problems when used with certain AGP video cards.
- Remove the drivers, restart the system, and reinstall the drivers from scratch.
- Remove the drivers, shut down the system, and relocate the audio adapter to a different PCI slot. When the system restarts, reinstall the drivers from scratch.
- If none of that works, suspect either a defective audio adapter or a fundamental incompatibility between your audio adapter and the rest of your system. Remove the drivers, shut down the system, remove the audio adapter, install a different audio adapter, and reinstall the drivers for it. If the replacement audio adapter is the same model and exhibits the same symptoms, try installing a different model of audio adapter.
If the problem occurs on a previously working system, take the following steps in order:
- If you have recently added or changed any hardware, check Device Manager to verify that no resource conflicts exist.
- If you have recently installed or uninstalled any software, it's possible that Setup installed DLLs that are incompatible with your audio adapter, or removed DLLs that your audio adapter or applications require. Remove the audio adapter drivers and reinstall them from scratch.
- If the sound still does not function properly, suspect an audio adapter failure.
Here are some specific common sound problems and their solutions:
This is probably the most common sound problem, and can have many causes. Following the troubleshooting steps just listed should resolve the problem.
This problem can also have many causes. Perhaps the most common is the audio adapter itself. Older and inexpensive audio adapters often have poor audio quality. Other common causes include a defective or low-quality audio cable, speakers placed too close to the monitor or other source of electrical noise, and the placement of the audio adapter within the system. If you have a choice, locate an audio adapter as far as possible from other expansion cards. Another possible cause is that some video card drivers are optimized for benchmark tests by having them keep control of the bus. The result can be intermittent dropouts and scratchiness in the sound.
Computer sound is digital, and is delivered directly to the audio adapter via the bus. Some old CD-ROM drives require a separate internal cable joining the audio-out connector on the back of the CD-ROM drive to the CD-audio connector on the audio adapter. If you do not have the necessary cable, you can temporarily fix the problem by connecting a standard stereo audio cable from the headphone jack on the front of the CD-ROM drive to the Line-in jack on the audio adapter. Note that modern motherboards and optical drives can deliver CD audio as a digital signal directly to the audio adapter, obviating the need for a separate CD audio cable.
If you have another set of speakers or headphones, connect them directly to the audio adapter Line-out port to isolate the problem to either the audio adapter or the speakers. Roughly in order of decreasing probability, the most likely causes and solutions are:
- The Windows audio balance control is set fully in one direction. Double-click the speaker icon in the System Tray and verify balance settings in the Volume Control dialog (or the replacement applet installed with your audio adapter drivers).
- The balance control on your speakers, if present, may be set fully in one direction. This happens commonly when someone blindly attempts to change volume or tone and turns the wrong knob. Center the speaker balance control.
- The audio cable is defective. Many audio cables, particularly those supplied with inexpensive speakers, are constructed poorly. Replace it with a high-quality, shielded audio cable, available for a few dollars from computer stores, audio specialty stores, and big-box stores.
- The audio cable is not fully seated in either the audio adapter jack or the speaker jack. Verify that the cable is fully seated at both ends.
- You are using a mono rather than stereo audio cable to connect Line-out on the audio adapter to the speakers. Replace the cable.
- The audio adapter driver is not installed, is installed improperly, or is the wrong driver. Some audio adapters may function partially under these conditions, and the most common symptom is single channel audio. Uninstall any driver currently installed, and then reinstall the proper driver.
- Although it is rare, we once encountered a set of amplified speakers with one channel dead and the other working. Replace the speakers.
This is by design in some audio adapters. Installing the card and driver intentionally disables the PC speaker and routes sounds that would ordinarily go to the PC speaker to the audio adapter instead.
On Windows systems with properly configured and functioning audio adapters, sound may disappear entirely for no apparent reason. This has happened to us on many different systems, under different versions of Windows, using different motherboards and audio adapters. The audio adapter still shows as installed, and everything appears perfectly normal, but the system simply stops sending audio to the speakers. This problem may or may not be accompanied by the speaker icon disappearing from the system tray. We have no idea what causes this, and we've never been able to get a satisfactory explanation from Microsoft. Restarting the system normally solves the problem, until next time. On systems where "next time" is all too frequent, we have occasionally had some success by removing and then reinstalling the sound drivers.
This problem normally results from a severe resource conflict or an improperly installed card. Verify first that the card is seated fully. If so, boot the system in Safe Mode or using the Last Known Good Configuration. With the system booted, determine which devices and resources are conflicting, resolve the conflicts, and restart the system.
This is usually caused by an interrupt conflict, often with the keyboard. Remove the keyboard in Device Manager, shut down and power off, and restart with just the mouse connected. If that solves the problem, turn off the system, reconnect the keyboard, and restart. If the problem persists, try moving the audio card to a different PCI slot or using a USB keyboard.