After downloading the ZIP file, extract it and you'll get an EXE file "sndvol32.exe". Now you just need to replace existing "sndvol32.exe" file present in "%windir%\System32" folder (here %windir% represents "Windows" folder present in the system drive where Windows is installed in your system) with this new one.
Make sure you have run WFP Patcher in Windows. WFP Patcher disables WFP (Windows File Protection) service which protects editing/replacing of system files and you'll not be able to replace the file until you disable it using WFP patcher. You may use Replacer: Download Now
