Win7 notebook sound, noise solution

The author recently found a strange phenomenon. When the notebook is watching HD movies under Win XP, the picture is smooth and the sound quality is very good. However, after upgrading to Windows 7, although the picture is not stuck, there is a phenomenon of popping and noise, and the driver is upgraded. The same is true for replacing the video player. Since it is normal under Win XP, it can eliminate hardware failures, and even if the upgrade driver has popping or noise, there is no driver compatibility problem. Query a large amount of information to know that this may be caused by the Win7 video optimization mechanism.

In Windows 7, Microsoft gives multimedia playback files a higher priority, trying to optimize multimedia (playback) performance by controlling the CPU, which optimizes HD performance for mainstream books, but for netbooks or configurations. The low old ones will have negative effects, such as a high CPU usage, a fake crash, or a popping or murmur when playing HD video.

Solution

To cancel the priority of Win7 video playback, enter the registry editor, expand to HKEY_LOCAL_MACHINE\\SYSTEM\\CurrentControlSet\\services\\Audiosrv, double click on the right window. ;DependOnService” name, then delete the “MMCSS” value in the dialog (Figure 1).
Figure 1 Delete MMCSS (do not delete other values) Exit Registry Editor, enter "lds; msconfig" in the Start menu "Search Programs and Files" box and press Enter (Figure 2), Figure 2 Run &ldquo The msconfig” command switches to the "Services" tab to locate and cancel the "Multimedia Class Scheduler" service (Figure 3). Figure 3 Unchecked “Multimedia Class Scheduler” After clicking the “Apply” button, restart the notebook and play the HD movie again, there will be no slow voice. Emphasize that the "pop" & rdquo; & quoquo; murmurs are not the problems that occur when playing high quality MP3 files. However, problems that occur when playing high-quality MP3 files, and problems that occur when playing HD movies, can be solved in the same way.