[DELPHI] Problem z WaveOutSetVolume pod Vistą

Witam.
Problem jak w temacie.
Próbuję zrobić program który zmienia głośność systemu.
Nie wiem czy to sprawka Visty czy czegoś innego, ale po prostu funkcja WaveOutSetVolume nie działa.
Szukałem prawie wszędzie, ale znalazłem tylko jeden program dzięki któremu regulacja działa, lecz z tego kodu nic się nie wyznam. Oto on:

unit Unit1;

interface

uses
  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
  Dialogs, StdCtrls, OleCtrls, MMsystem;

type
  TForm1 = class(TForm)
    CheckBox1: TCheckBox;
    Button1: TButton;
    Edit1: TEdit;
    Button2: TButton;
    procedure Button2Click(Sender: TObject);
    procedure Button1Click(Sender: TObject);
    procedure Button3Click(Sender: TObject);
    procedure FormClick(Sender: TObject);
    procedure FormCreate(Sender: TObject);
    procedure BtnVocalClick(Sender: TObject);
  private
    { Private 錾 }
  public
    { Public 錾}
  end;

var
  Form1: TForm1;
  OS: String;

implementation

{$R *.dfm}

uses MMDeviceApi, ActiveX, ComObj, StdConvs;

procedure SetVolumeChannel(Channel:byte);
var Lvol, RVol, LValue, RValue, temp: DWord;
begin
  // WaveoutGetVolume() retrieves the current volume
  WaveoutGetVolume(WAVE_MAPPER, @temp);
  Lvol := Loword(temp);
  Rvol := hiword(temp);
  if channel = 0 then
  begin //Left Channel
    LValue := 65535;
    RValue := 0;
  end else if channel = 1 then begin //Right Channel
    LValue := 0;
    RValue := 65535;
  end else if channel = 2 then begin //Stereo Channel
    LValue := 65535;
    RValue := 65535;
  end else begin //Wrong Channel
    ShowMessage('Channel Salah');
  end;
  asm 
        shl Lvalue,16
        shl Rvalue,16
  end;
  LValue := LValue and $ffff0000;
  LValue := RValue and $ffff0000;
  WaveoutSetVolume(WAVE_MAPPER, LValue or Lvol);
  WaveoutSetVolume(WAVE_MAPPER, RValue or Rvol);
end;


function GetWinVersion: String;
var
   osVerInfo: TOSVersionInfo;
   majorVersion, minorVersion: Integer;
begin
   Result := 'wvUnknown';
   osVerInfo.dwOSVersionInfoSize := SizeOf(TOSVersionInfo) ;
   if GetVersionEx(osVerInfo) then
   begin
     minorVersion := osVerInfo.dwMinorVersion;
     majorVersion := osVerInfo.dwMajorVersion;
     case osVerInfo.dwPlatformId of
       VER_PLATFORM_WIN32_NT:
       begin
         if majorVersion <= 4 then
           Result := 'wvWinNT'
         else if (majorVersion = 5) and (minorVersion = 0) then
           Result := 'wvWin2000'
         else if (majorVersion = 5) and (minorVersion = 1) then
           Result := 'wvWinXP'
         else if (majorVersion = 6) then
           Result := 'wvWinVista';
       end;
       VER_PLATFORM_WIN32_WINDOWS:
       begin
         if (majorVersion = 4) and (minorVersion = 0) then
           Result := 'wvWin95'
         else if (majorVersion = 4) and (minorVersion = 10) then
         begin
           if osVerInfo.szCSDVersion[1] = 'A' then
             Result := 'wvWin98SE'
           else
             Result := 'wvWin98';
         end
         else if (majorVersion = 4) and (minorVersion = 90) then
           Result := 'wvWinME'
         else
           Result := 'wvUnknown';
       end;
     end;
   end;
end;


function GetAudioEndpointVolume:IAudioEndpointVolume;
var
  Enumerator: IMMDeviceEnumerator;
  Endpoint: IMMDevice;
  clsid: TGUID;
begin
  Result := nil;

  Enumerator := CreateComObject(CLASS_IMMDeviceEnumerator) as IMMDeviceEnumerator;

  if Failed( Enumerator.GetDefaultAudioEndpoint(eRender, eConsole, Endpoint)) then Exit;

  clsid := IID_IAudioEndpointVolume;
  if Failed( Endpoint.Activate(clsid, CLSCTX_ALL, nil, IUnknown(Result))) then Exit;

end;

procedure TForm1.Button1Click(Sender: TObject);
var
  AudioEndVol: IAudioEndpointVolume;
  Vol: Single;
  Mute: LongBool;
begin
  AudioEndVol := GetAudioEndpointVolume;

  if not Assigned(AudioEndVol) then Exit;

  if Failed( AudioEndVol.GetMasterVolumeLevelScalar(Vol)) then Exit;
  Edit1.Text := FloatToStr(Vol);

  if Failed( AudioEndVol.GetMute(Mute)) then Exit;
  CheckBox1.Checked := Mute;

end;

procedure TForm1.Button2Click(Sender: TObject);
var
  AudioEndVol: IAudioEndpointVolume;
begin
  AudioEndVol := GetAudioEndpointVolume;

  if not Assigned(AudioEndVol) then Exit;

  if Failed( AudioEndVol.SetMasterVolumeLevelScalar(StrToFloat(Edit1.Text), @GUID_NULL)) then Exit;
  if Failed( AudioEndVol.SetMute(LongBool(CheckBox1.Checked), @GUID_NULL)) then Exit;

end;

procedure TForm1.FormClick(Sender: TObject);
var
  AudioEndVol: IAudioEndpointVolume;
begin
  AudioEndVol := GetAudioEndpointVolume;
  if not Assigned(AudioEndVol) then Exit;
  AudioEndVol.SetChannelVolumeLevel(0,0,@GUID_NULL);
  AudioEndVol.SetChannelVolumeLevel(1,0,@GUID_NULL);

end;

procedure TForm1.FormCreate(Sender: TObject);
var
  AudioEndVol: IAudioEndpointVolume;
  saluran:cardinal;
  i : byte;
begin
  OS := GetWinVersion();
  if (OS='wvWinVista') then
  begin
    AudioEndVol := GetAudioEndpointVolume;
    if not Assigned(AudioEndVol) then Exit;
    AudioEndVol.GetChannelCount(saluran);
    CBChannel.Clear;
    for i := 0 to saluran-1 do
    begin
      CBChannel.Items.Add(inttostr(i));
    end;
  end else
    GBSound.Enabled := false;
end;

procedure TForm1.BtnVocalClick(Sender: TObject);
var
  AudioEndVol: IAudioEndpointVolume;
begin
  if BtnVocal.Caption = 'Vocal ON' then
  begin
    BtnVocal.Caption := 'Vocal OFF';
    if OS = 'wvWinVista' then
    begin
      AudioEndVol := GetAudioEndpointVolume;
      if not Assigned(AudioEndVol) then Exit;
      AudioEndVol.SetChannelVolumeLevel(1,-64,@GUID_NULL);
    end else begin
      SetVolumeChannel(1);
    end;
  end else if BtnVocal.Caption = 'Vocal OFF' then
  begin
    BtnVocal.Caption := 'Vocal ON';
    if OS = 'wvWinVista' then
    begin
      AudioEndVol := GetAudioEndpointVolume;
      if not Assigned(AudioEndVol) then Exit;
      AudioEndVol.SetChannelVolumeLevel(1,0,@GUID_NULL);
    end else begin
      SetVolumeChannel(2);
    end;
  end;

end;

Z góry dziękuję za pomoc.
Pozdrawiam

RampleR