FIX: Noticeable problems occur in the video when you use the DirectSound renderer on Windows Vista

When you use the DirectSound audio renderer on Windows Vista to play audio and video, noticeable problems occur in the video if a gap exists in the audio data. This problem occurs if you are using an audio bit depth that is larger than 16-bit depth.

The DirectSound audio renderer usually inserts silence into an audio stream when gaps exist in the data. However, this does not work for audio bit depths that are larger than 16-bit depth, such as 24-bit depth or 32 bit-depth. Because both the audio and video in Windows are synchronized to the audio sample clock, the gaps in the audio cause video to render late. This causes noticable problems during playback.

Hotfix information

A supported hotfix is now available from Microsoft. However, it is intended to correct only the problem that this article describes. Apply it only to systems that are experiencing this specific problem.

To resolve this problem, obtain the hotfix from the Microsoft Download Center.

Download information

The following files are available for download from the Microsoft Download Center:

Windows Vista, 32-bit versions (all languages)

Download the Windows6.0-KB950754-x86.msu package now. (http://download.microsoft.com/download/1/1/E/11E6CC02-8660-4FB5-B03C-475D50F592D9/Windows6.0-KB950754-x86.msu)

Windows Vista, 64-bit versions (all languages)

Download the Windows6.0-KB950754-x64.msu package now. (http://download.microsoft.com/download/1/1/E/11E6CC02-8660-4FB5-B03C-475D50F592D9/Windows6.0-KB950754-x64.msu)

For more information about how to download Microsoft support files, click the following article number to view the article in the Microsoft Knowledge Base: Microsoft scanned this file for viruses. Microsoft used the most current virus-detection software that was available on the date that the file was posted. The file is stored on security-enhanced servers that help prevent any unauthorized changes to the file.

Prerequisites

You must have Windows Vista Service Pack 1 (SP1) installed.

Restart requirement

You do not have to restart your computer after you apply this hotfix.

Hotfix replacement information

This hotfix does not replace any other previously released hotfixes.

Registry information

To use this hotfix, you do not have to make any changes to the registry.

The global version of this hotfix has the file attributes (or later file attributes) that are listed in the following table. The dates and times for these files are listed in Coordinated Universal Time (UTC). When you view the file information, it is converted to local time. To find the difference between UTC and local time, use the Time Zone tab in the Date and Time item in Control Panel.

Microsoft has confirmed that this is a bug in the Microsoft products that are listed in the "Applies to" section.

For example, you may have this problem if you receive a digital video signal over an antenna, and there are occasional reception problems. If any loss of audio data occurs, the video playback is affected.