Microsoft KB Archive/265523

= How to Troubleshoot Audio and Video Issues in Windows Media Player =

Article ID: 265523

Article Last Modified on 5/7/2007

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APPLIES TO


 * Microsoft Windows Media Player 7.0

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This article was previously published under Q265523



SUMMARY
This article describes the issues that may impact the quality of media that is played in Windows Media Player, and the general troubleshooting steps that you can perform to overcome these issues.

The following issues are described in this article:
 * Inferior quality
 * Random flashes
 * Audio or video plays, but not both
 * Audio plays on some clips
 * Audio sounds hiss, pop, sound scratchy, or fluctuate



Issue:
You can play media content in Media Player, but the quality is inferior.

Cause:
Windows Media Technologies content is created for specific bandwidth ranges. If the content is created for a 28.8 Kilobits per second (Kbps) or 56 Kbps connection, but Internet traffic is heavy, the NetShow Services server may start to drop the frame rate (the number of frames each second) to compensate for the increased network congestion. This behavior can cause the video image to become &quot;jerky&quot; and uneven.

The quality of the audio or video may also be inferior because of the compression choices of the content creator. When you compress the content for playing over constrained-bandwidth networks (such as the Internet), mathematical algorithms called codecs are applied to the content. Codecs are used for compressing and decompressing digital media. The codec selection of the content creator greatly influences the quality of the video and audio. For example, if the content creator prioritized audio quality over video quality (or the frame rate), the audio may play correctly, but the video may not play correctly.

Troubleshooting:
Attempt to play the content again when your connection is better, or ensure that you have selected the content that is targeted for the bandwidth that you have available.

You can also test the media content using the Mplayer2.exe program, which is located in the C:\Program Files\Windows Media Player folder. If MPlayer2 is able to properly play the media, check for network and performance configuration issues in Windows Media Player.

Issue:
When you play video, it may display random flashes of pink, green, or spots.

Cause:
Typically, this issue is associated with certain display adapter drivers that have difficulty with some DirectDraw features that Windows Media Player uses.

Troubleshooting:
In many cases, if you update the drivers for your display adapter, the issue is corrected. If this issue is not corrected, run the DirectX Diagnostic Tool to test DirectDraw functionality.

For additional information about troubleshooting DirectDraw issues, click the article number below to view the article in the Microsoft Knowledge Base:

190900 DirectX: Description of the DirectX Diagnostic Tool

Issue:
The audio plays, but the video does not, or vice-versa.

Troubleshooting:
As a first step, ensure that your computer has a sound card installed. If your computer has a sound card, the content probably uses a compression codec that is not installed on your computer. To ensure that you have all of the codecs installed on your computer that are currently supported, reinstall Windows Media Player from the following Microsoft Web site:

http://www.microsoft.com/windows/windowsmedia/download

Other Cause:
This issue may also occur if there is not enough bandwidth to play both audio and video. You may receive sound, even though the video is not present because audio requires less available bandwidth.

Issue:
You can hear the audio on some clips, but not on other clips.

Cause:
This issue can involve a number of causes, very few of which can be corrected in the player. To verify that the issue is not a player issue, refer to the following Troubleshooting section.

Troubleshooting:
Verify that you have the correct and up-to-date drivers for your sound card. The use of incorrect or out-of-date drivers can result in unexpected behavior.

Some sound cards are incapable of playing audio content that had been created with either an 8 Kilohertz (kHz) or 16 kHz sampling rate. To determine if the sampling rate is the issue, check the sampling rate that is used in the .asf file. In Windows Media Player, open the &quot;problem&quot; streaming media file. On the File menu, click Properties. Beside Audio Codec, the sampling rate that is used for the audio is listed, for example, 44 kHz. If the sampling rate is 8 kHz or 16 kHz, this rate can be the cause of the problem.

For additional information about specific file formats, refer to the Windows Media Player File Format test page at the following Microsoft Web site:

Windows Media Player 7 Multimedia File Formats

Issue:
You can hear the audio, but the audio hisses, pops, sounds &quot;scratchy&quot;, or fluctuates.

Cause and Troubleshooting:
Verify that you have the proper and most up-to-date drivers for your sound card. NetShow Services uses standard Windows compression codecs to compress and decompress the audio. You may have a poorly implemented or incorrect sound card driver that can cause problems with compressed audio. Also, you may be using improper or outdated sound card drivers without realizing it because all of the computer sounds that are included with Windows are uncompressed audio files that can often be played even with incorrect or mismatched drivers. This issue is not unique to NetShow Services as any multimedia program that uses Windows sound codecs and compressed audio files may exhibit similar behavior.

Additional query words: sound mplayer2 wmp

Keywords: kbinfo kbtshoot KB265523

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