PSAutoMute

1.0.1

PSAutoMute.ps1

<#PSScriptInfo
 
.VERSION 1.0.1
 
.GUID 4d1438ae-0691-4fa4-8fdf-3ef8e73db79f
 
.AUTHOR PrateekSingh
 
.COMPANYNAME
 
.COPYRIGHT
 
.TAGS Powershell audio api
 
.LICENSEURI
 
.PROJECTURI https://geekeefy.wordpress.com/2017/03/31/powershell-auto-mute-when-headphones-are-accidently-unplugged/
 
.ICONURI
 
.EXTERNALMODULEDEPENDENCIES
 
.REQUIREDSCRIPTS
 
.EXTERNALSCRIPTDEPENDENCIES
 
.RELEASENOTES
 
 
#>

<#
 
.DESCRIPTION
 Powershell script to Auto Mute you sound devices like headphones, if they are accidently unplugged.
 
#> 

[cmdletbinding()]
Param()

#Adding definitions for accessing the Audio API
Add-Type -TypeDefinition @'
using System.Runtime.InteropServices;
[Guid("5CDF2C82-841E-4546-9722-0CF74078229A"), InterfaceType(ComInterfaceType.InterfaceIsIUnknown)]
interface IAudioEndpointVolume {
  // f(), g(), ... are unused COM method slots. Define these if you care
  int f(); int g(); int h(); int i();
  int SetMasterVolumeLevelScalar(float fLevel, System.Guid pguidEventContext);
  int j();
  int GetMasterVolumeLevelScalar(out float pfLevel);
  int k(); int l(); int m(); int n();
  int SetMute([MarshalAs(UnmanagedType.Bool)] bool bMute, System.Guid pguidEventContext);
  int GetMute(out bool pbMute);
}
[Guid("D666063F-1587-4E43-81F1-B948E807363F"), InterfaceType(ComInterfaceType.InterfaceIsIUnknown)]
interface IMMDevice {
  int Activate(ref System.Guid id, int clsCtx, int activationParams, out IAudioEndpointVolume aev);
}
[Guid("A95664D2-9614-4F35-A746-DE8DB63617E6"), InterfaceType(ComInterfaceType.InterfaceIsIUnknown)]
interface IMMDeviceEnumerator {
  int f(); // Unused
  int GetDefaultAudioEndpoint(int dataFlow, int role, out IMMDevice endpoint);
}
[ComImport, Guid("BCDE0395-E52F-467C-8E3D-C4579291692E")] class MMDeviceEnumeratorComObject { }
public class Audio {
  static IAudioEndpointVolume Vol() {
    var enumerator = new MMDeviceEnumeratorComObject() as IMMDeviceEnumerator;
    IMMDevice dev = null;
    Marshal.ThrowExceptionForHR(enumerator.GetDefaultAudioEndpoint(/*eRender*/ 0, /*eMultimedia*/ 1, out dev));
    IAudioEndpointVolume epv = null;
    var epvid = typeof(IAudioEndpointVolume).GUID;
    Marshal.ThrowExceptionForHR(dev.Activate(ref epvid, /*CLSCTX_ALL*/ 23, 0, out epv));
    return epv;
  }
  public static float Volume {
    get {float v = -1; Marshal.ThrowExceptionForHR(Vol().GetMasterVolumeLevelScalar(out v)); return v;}
    set {Marshal.ThrowExceptionForHR(Vol().SetMasterVolumeLevelScalar(value, System.Guid.Empty));}
  }
  public static bool Mute {
    get { bool mute; Marshal.ThrowExceptionForHR(Vol().GetMute(out mute)); return mute; }
    set { Marshal.ThrowExceptionForHR(Vol().SetMute(value, System.Guid.Empty)); }
  }
}
'@ -Verbose


While($true)
{
    #Clean all events in the current session since its in a infinite loop, to make a fresh start when loop begins
    Get-Event | Remove-Event -ErrorAction SilentlyContinue

    #Registering the Event and Waiting for event to be triggered
    Register-WmiEvent -Class Win32_DeviceChangeEvent
    Wait-Event -OutVariable Event |Out-Null

    $EventType = $Event.sourceargs.newevent | `
    Sort-Object TIME_CREATED -Descending | `
    Select-Object EventType -ExpandProperty EventType -First 1

    #Conditional logic to handle, When to Mute/unMute the machine using Audio API
    If($EventType -eq 3)  
    {
        [Audio]::Mute = $true
        Write-Verbose "Muted [$((Get-Date).tostring())]"
    }
    elseif($EventType -eq 2 -and [Audio]::Mute -eq $true)
    {
        [Audio]::Mute = $false
        Write-Verbose "UnMuted [$((Get-Date).tostring())]"
    }
}