A MIDI capture program does not work correctly on a Windows XP-based computer that has a dual-core or hyper-threading processor

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You use a Musical Instrument Digital Interface (MIDI) capture program on a Microsoft Windows XP-based computer. The computer has a dual-core or hyper-threading processor. However, the MIDI capture program does not work correctly. Specifically, the MIDI data is corrupted.

Hotfix information

A supported hotfix is available from Microsoft. However, this hotfix is intended to correct only the problem that is described in this article. Apply this hotfix only to systems that are experiencing this specific problem. This hotfix might receive additional testing. Therefore, if you are not severely affected by this problem, we recommend that you wait for the next software update that contains this hotfix.

If the hotfix is available for download, there is a "Hotfix download available" section at the top of this Knowledge Base article. If this section does not appear, contact Microsoft Customer Service and Support to obtain the hotfix.

Note If additional issues occur or if any troubleshooting is required, you might have to create a separate service request. The usual support costs will apply to additional support questions and issues that do not qualify for this specific hotfix. For a complete list of Microsoft Customer Service and Support telephone numbers or to create a separate service request, visit the following Microsoft Web site: Note The "Hotfix download available" form displays the languages for which the hotfix is available. If you do not see your language, it is because a hotfix is not available for that language.

File information

The English 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.
File nameFile versionFile sizeDateTimePlatform
To work around this problem, configure the dual-core or hyper-threading processor to use only one processor. To do this, add the /Numproc switch to the Boot.ini file, and then apply a setting of 1. You can use the Microsoft System Configuration Utility to make this change.

Note This workaround may affect the computer's performance. You may want to use this switch only when you are using the MIDI capture program. In this situation, delete the switch when you are not using the MIDI capture program.

Add the /Numproc switch

  1. Click Start, click Run, type msconfig, and then click OK.
  2. Click the BOOT.INI tab.
  3. Click Advanced Options.
  4. Click to select the /NUMPROC= check box, and then click 1 in the /NUMPROC= box.
  5. Click OK two times, and then restart the computer.
Note After you restart the computer, the System Configuration Utility (Msconfig.exe) also starts. To restore the computer to its previous state, use the "Delete the /Numproc switch" method.

Delete the /Numproc switch

  1. Click Start, click Run, type msconfig, and then click OK.
  2. Click the General tab.
  3. Click Normal Startup - load all device drivers and services.
  4. Click OK, and then restart the computer.
Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.
More information
For more information, click the following article number to view the article in the Microsoft Knowledge Base:
824684Description of the standard terminology that is used to describe Microsoft software updates
USB Audio usbaudio.sys

Article ID: 919484 - Last Review: 01/16/2015 09:13:46 - Revision: 4.0

Microsoft Windows XP Professional, Microsoft Windows XP Home Edition

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