Windows Vista · Workaround

Workaround for LSM.EXE Handle and Memory Leak

Kristan Kenney · · Restored archive post · Edited by Muhd Radhi Wahab
Restored from the windows-now.com archive. This post was originally published by Kristan Kenney on 21 May 2007. It is reproduced faithfully for its historical and reference value, with the original author and date credited. A present-day editor's note follows the original text. If you are the author and would like this amended or removed, contact us.

Consider the following scenario. If you have a computer that uses a high definition audio device, which is running Microsoft Windows Vista, and you are using Windows Media Player 11, handles and memory may be lost because of a leak in the Lsm.exe process.

As you fast forward through your Windows Media Player library, or have a playlist set to repeat, you may lose a large amount of handles in a short amount of time. This can lead to performance degradation and in some cases, "out of memory" error messages and other unexpected behavior. If you review the Task Manager you may notice that Lsm.exe is consuming a large amount of memory.

This issue only occurs if the following statements are true:

  • Your computer utilizes a High Definition Audio Device
  • You are running Windows Vista, or Windows Vista 64-bit.
  • You are using Windows Media Player 11 to play back audio files.

There is a hotfix available from Microsoft to resolve this issue, however in some cases this may not resolve the issue. The following workaround is a method that I have tested on several systems that exhibit this issue and have found that it does indeed resolve the issue.

  • Click on Start, and then click on Control Panel.
  • Click on Hardware and Sound.
  • Under Sound, click on "Manage audio devices".
  • Select your output device in the list that appears (the default output devices is commonly labelled "Speakers")
  • Right click on the device and from the context menu click on Properties.
  • In the "Properties" window, click on the "Enhancements" tab.
  • Tick/check the option box for "Disable all enhancements".
  • Click on OK to dismiss the properties window.
  • Click on OK to dismiss the "Sound" window.
  • Close the Control Panel window by clicking the Close ("X") button at the top right of the window.

NOTE: You will have to restart your computer in order to reclaim previously lost memory and handles.

Editor's note — context in 2026

This workaround dates from the Windows Vista and Windows Media Player 11 era. The Lsm.exe leak described here was specific to that combination on High Definition Audio hardware, and Microsoft's hotfix KB933245 targeted it directly. On modern Windows there is no equivalent Lsm.exe audio leak to fix, but the underlying step — turning off audio "enhancements" for a playback device — still exists: on Windows 10 and 11 you disable per-device effects under Settings → System → Sound (or the classic Sound control panel) if an output device behaves oddly. The 2007 steps above are preserved unchanged for accuracy.

Frequently asked

Which systems are affected by the Lsm.exe handle and memory leak?

The issue only occurs when all of these are true: your computer uses a High Definition Audio Device, you are running Windows Vista or Windows Vista 64-bit, and you are using Windows Media Player 11 to play back audio files.

How do you work around the leak if the Microsoft hotfix does not help?

Open Control Panel, go to Hardware and Sound, click Manage audio devices, open the Properties of your output device, and on the Enhancements tab tick Disable all enhancements. You must then restart the computer to reclaim previously lost memory and handles.