Get/Set Master Volume Lautstärke?

[PeterPanino]

Debugging it further:

Delphi-Quellcode:

procedure TForm1.SetMasterVolumeMuteState(Muted: Boolean);
var
  MuteStatus: Boolean;
  FAudioEndpointVolume: AudioEndpoint.IAudioEndpointVolume; // from the Andreas Rejbrand unit
  FDeviceEnumerator: IMMDeviceEnumerator;
  FMMDevice: IMMDevice;
begin
  CodeSite.Send('TForm1.SetMasterVolumeMuteState: A');
  if not Succeeded(CoCreateInstance(CLASS_IMMDeviceEnumerator, nil, CLSCTX_INPROC_SERVER,
    IID_IMMDeviceEnumerator, FDeviceEnumerator)) then
  begin
    //OutputDebugString('TForm1.SetMasterVolumeLevelScalar: 1');
    CodeSite.Send('TForm1.SetMasterVolumeLevelScalar: 1');
    ExitProcess(1);
  end;

  if not Succeeded(FDeviceEnumerator.GetDefaultAudioEndpoint(0, 0, FMMDevice)) then
  begin
    //OutputDebugString('TForm1.SetMasterVolumeLevelScalar: 2');
    CodeSite.Send('TForm1.SetMasterVolumeLevelScalar: 2');
    ExitProcess(1);
  end;

  if not Succeeded(FMMDevice.Activate(IID_IAudioEndpointVolume, CLSCTX_INPROC_SERVER, nil, FAudioEndpointVolume)) then
  begin
    //OutputDebugString('TForm1.SetMasterVolumeLevelScalar: 3');
    CodeSite.Send('TForm1.SetMasterVolumeLevelScalar: 3');
    ExitProcess(1);
  end;

  CodeSite.Send('TForm1.SetMasterVolumeMuteState: B');

  if Assigned(FAudioEndpointVolume) then
  begin
    CodeSite.Send('TForm1.SetMasterVolumeMuteState: C');
    var R: System.HResult := FAudioEndpointVolume.SetMute(Muted, nil);
    case R of
      S_OK:          CodeSite.Send('TForm1.SetMasterVolumeMuteState: OK');          // successful operation with a return value of True
      S_FALSE:       CodeSite.Send('TForm1.SetMasterVolumeMuteState: FALSE');       // successful operation with a return value of False
      E_NOINTERFACE: CodeSite.Send('TForm1.SetMasterVolumeMuteState: NOINTERFACE'); // Interface not supported
      E_UNEXPECTED:  CodeSite.Send('TForm1.SetMasterVolumeMuteState: UNEXPECTED');  // Catastrophic failure
      E_NOTIMPL:     CodeSite.Send('TForm1.SetMasterVolumeMuteState: NOTIMPL');     // Operation not implemented
      else           CodeSite.Send('TForm1.SetMasterVolumeMuteState: ELSE');
    end;
  end
  else
  begin
    //OutputDebugString('TForm1.SetMasterVolumeLevelScalar: FAudioEndpointVolume not assigned!');
    CodeSite.Send('TForm1.SetMasterVolumeLevelScalar: FAudioEndpointVolume not assigned!');
  end;
end;

When calling SetMasterVolumeMuteState(True);

I get these debug messages:

TForm1.SetMasterVolumeMuteState: A
TForm1.SetMasterVolumeMuteState: B
TForm1.SetMasterVolumeMuteState: C
TForm1.SetMasterVolumeMuteState: ELSE

[Kas Ob.]

Zitat:

Isn't the logic inverted here? (if not Succeeded -> SetMute OK)

Yes you are right there.

I messed that up, but in all cases the master is switching between muted and unmuted with that function, try to capture the R value.

Also it seems the behavior is different on my Windows
AudioEndpoint.jpg

As you see in the Log Event first click is OK showing changing state followed by False because the state is not changed.

[PeterPanino]

Catching the R value on ELSE:

When calling SetMasterVolumeMuteState(True);

I get these debug messages:

TForm1.SetMasterVolumeMuteState: A
TForm1.SetMasterVolumeMuteState: B
TForm1.SetMasterVolumeMuteState: C
TForm1.SetMasterVolumeMuteState: ELSE = -2147024809

"-2147024809" is "0x80070057," which corresponds to the error code E_INVALIDARG (Invalid arguments).

How do you call SetMute?

[Kas Ob.]

Here is my full working example

Code:

procedure TForm10.Button3Click(Sender: TObject);
begin
  SetMasterMuteState(True);
end;

procedure TForm10.Button4Click(Sender: TObject);
begin
  SetMasterMuteState(False);
end;

procedure TForm10.SetMasterMuteState(Muted: Boolean);
var
  MuteStatus: Boolean;
  FAudioEndpointVolume: AudioEndpoint.IAudioEndpointVolume; // from the Andreas Rejbrand unit
  FDeviceEnumerator: IMMDeviceEnumerator;
  FMMDevice: IMMDevice;
  R: System.HResult;
begin
  if not Succeeded(CoCreateInstance(CLASS_IMMDeviceEnumerator, nil, CLSCTX_INPROC_SERVER,
    IID_IMMDeviceEnumerator, FDeviceEnumerator)) then
  begin
    OutputDebugString('TForm1.SetMasterVolumeLevelScalar: 1');
      //CodeSite.Send('TForm1.SetMasterVolumeLevelScalar: 1');
    ExitProcess(1);
  end;

  if not Succeeded(FDeviceEnumerator.GetDefaultAudioEndpoint(0, 0, FMMDevice)) then
  begin
    OutputDebugString('TForm1.SetMasterVolumeLevelScalar: 2');
      //CodeSite.Send('TForm1.SetMasterVolumeLevelScalar: 2');
    ExitProcess(1);
  end;

  if not Succeeded(FMMDevice.Activate(IID_IAudioEndpointVolume, CLSCTX_INPROC_SERVER, nil,
    FAudioEndpointVolume)) then
  begin
    OutputDebugString('TForm1.SetMasterVolumeLevelScalar: 3');
      //CodeSite.Send('TForm1.SetMasterVolumeLevelScalar: 3');
    ExitProcess(1);
  end;

  if Assigned(FAudioEndpointVolume) then
  begin

      R := FAudioEndpointVolume.SetMute(Muted, nil);
    case R of
      S_OK: OutputDebugString('TForm1.SetMasterVolumeMuteState: OK'); // successful operation with a return value of True
      S_FALSE: OutputDebugString('TForm1.SetMasterVolumeMuteState: FALSE'); // successful operation with a return value of False
      E_NOINTERFACE: OutputDebugString('TForm1.SetMasterVolumeMuteState: NOINTERFACE'); // Interface not supported
      E_UNEXPECTED: OutputDebugString('TForm1.SetMasterVolumeMuteState: UNEXPECTED'); // Catastrophic failure
      E_NOTIMPL: OutputDebugString('TForm1.SetMasterVolumeMuteState: NOTIMPL'); // Operation not implemented
      else OutputDebugString(PChar('TForm1.SetMasterVolumeMuteState: ELSE '+ IntToHex(R,8)));
    end;

  end
  else
  begin
    OutputDebugString('TForm1.SetMasterVolumeLevelScalar: FAudioEndpointVolume not assigned!');
      //CodeSite.Send('TForm1.SetMasterVolumeLevelScalar: FAudioEndpointVolume not assigned!');
  end;
end;

[PeterPanino]

TForm1.FormKeyUp:
TForm1.SetMasterVolumeMuteState: A
TForm1.SetMasterVolumeMuteState: B
TForm1.SetMasterVolumeMuteState: C
TForm1.SetMasterVolumeMuteState: ELSE 80070057

There must be a difference between our versions of Windows.

[Kas Ob.]

Interesting !

Please try this

Code:

const
  IID_IAudioEndpointVolumeEx: TGUID = '{66E11784-F695-4F28-A505-A7080081A78F}';

type
  IAudioEndpointVolumeEx = interface(IAudioEndpointVolume)
    [IID_IAudioEndpointVolumeEx]
    function GetVolumeRangeChannel(nChannel: Integer; out pflVolumeMindB: double; out
      pflVolumeMaxdB: double; out pflVolumeIncrementdB: double): HRESULT; stdcall;
  end;

procedure TForm10.Button3Click(Sender: TObject);
begin
  SetMasterMuteState(True);
end;

procedure TForm10.Button4Click(Sender: TObject);
begin
  SetMasterMuteState(False);
end;

procedure TForm10.SetMasterMuteState(Muted: Boolean);
var
  FAudioEndpointVolumeEx: IAudioEndpointVolumeEx;
  FDeviceEnumerator: IMMDeviceEnumerator;
  FMMDevice: IMMDevice;
  R: System.HResult;
begin
  if not Succeeded(CoCreateInstance(CLASS_IMMDeviceEnumerator, nil, CLSCTX_INPROC_SERVER,
    IID_IMMDeviceEnumerator, FDeviceEnumerator)) then
  begin
    OutputDebugString('TForm1.SetMasterVolumeLevelScalar: 1');
      //CodeSite.Send('TForm1.SetMasterVolumeLevelScalar: 1');
    ExitProcess(1);
  end;

  if not Succeeded(FDeviceEnumerator.GetDefaultAudioEndpoint(0, 0, FMMDevice)) then
  begin
    OutputDebugString('TForm1.SetMasterVolumeLevelScalar: 2');
      //CodeSite.Send('TForm1.SetMasterVolumeLevelScalar: 2');
    ExitProcess(1);
  end;

  if not Succeeded(FMMDevice.Activate(IID_IAudioEndpointVolumeEx, CLSCTX_INPROC_SERVER,
    nil, IAudioEndpointVolume(FAudioEndpointVolumeEx))) then
  begin
    OutputDebugString('TForm1.SetMasterVolumeLevelScalar: 3');
      //CodeSite.Send('TForm1.SetMasterVolumeLevelScalar: 3');
    ExitProcess(1);
  end;

  if Assigned(FAudioEndpointVolumeEx) then
  begin
    R := FAudioEndpointVolumeEx.SetMute(Muted, nil);
    case R of
      S_OK:
        OutputDebugString('TForm1.SetMasterVolumeMuteState: OK'); // successful operation with a return value of True
      S_FALSE:
        OutputDebugString('TForm1.SetMasterVolumeMuteState: FALSE'); // successful operation with a return value of False
      E_NOINTERFACE:
        OutputDebugString('TForm1.SetMasterVolumeMuteState: NOINTERFACE'); // Interface not supported
      E_UNEXPECTED:
        OutputDebugString('TForm1.SetMasterVolumeMuteState: UNEXPECTED'); // Catastrophic failure
      E_NOTIMPL:
        OutputDebugString('TForm1.SetMasterVolumeMuteState: NOTIMPL'); // Operation not implemented
    else
      OutputDebugString(PChar('TForm1.SetMasterVolumeMuteState: ELSE ' + IntToStr(R)));
    end;

  end
  else
  begin
    OutputDebugString('TForm1.SetMasterVolumeLevelScalar: FAudioEndpointVolume not assigned!');
      //CodeSite.Send('TForm1.SetMasterVolumeLevelScalar: FAudioEndpointVolume not assigned!');
  end;
end;

Also did you try to run your application as Administrator ? , it could be some permission problem.