A USB telephony device that is installed on a Windows Vista-based computer is unexpectedly set as the default audio device

After you install a universal serial bus (USB) telephony device on a Windows Vista-based computer, this device is unexpectedly set as the default audio device. The USB telephony device can be a USB telephone, a USB handset, or a USB headset. This behavior occurs even though other audio devices are already installed on the computer.

In this situation, the computer cannot correctly play media or record media.

This problem occurs because the system does not check the device type of the newly installed audio device. Instead, the system sets the newly installed device as the default audio device even though the device is a telephony device.

Service pack information

To resolve this problem, obtain the latest service pack for Windows Vista. For more information, click the following article number to view the article in the Microsoft Knowledge Base:

Hotfixes and security updates that are included in SP2 for Windows Vista Service and for Windows Server 2008

For more information about the hotfixes and the security updates that are included in SP2 for Windows Vista and for Windows Server 2008, visit the following Microsoft TechNet Web site: -Note: Currently, the list of hotfixes and security updates is available only in English.

Update information

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

Windows Vista, 32-bit versions

Download the 936004 package now. (http://www.microsoft.com/downloads/details.aspx?FamilyId=9B71C47E-149C-43F9-B641-61126CE82EE4)

Windows Vista, 64-bit versions

Download the 936004 package now. (http://www.microsoft.com/downloads/details.aspx?FamilyId=2A17B0E2-82A0-4C24-8055-EE9591DEBF3E)

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

No prerequisites are required.

Restart requirement

You must restart the computer after you apply this update.

Update replacement information

This update does not replace any other updates.

File information

The English version of this update 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.

Windows Vista, 32-bit versions

Windows Vista, 64-bit versions

To work around this problem, reset the device of your choice as the default audio device. To do this, follow these steps:

1. Click Start, and then click Control Panel.
2. In Control Panel, double-click Sound.
3. On the Playback tab, click the audio device that you want in the Select a playback device below to modify its settings list, and then click Set Default.
4. On the Recording tab, click the audio device that you want in the Select a playback device below to modify its settings list, and then click Set Default.
5. Click OK.

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

For more information about the same problem in Windows XP, click the following article number to view the article in the Microsoft Knowledge Base: For more information about how to determine an audio device type, visit the following Microsoft Web site: For more information, click the following article number to view the article in the Microsoft Knowledge Base: