Как вывести громкость звука системы?

{$R *.dfm}
type
 
  TRampArray = Array[0..2] of Array[Byte] of Word;
var
  OrigRampArray: TRampArray;
 
 
function setbrightness(wbrightness:word):boolean;
var 
ramparray:tramparray;
i:integer;
value:word;
dc:hdc; 
begin 
for i:=0 to maxbyte do 
begin 
value := i * (wbrightness + 128);
if (value > maxword) then value := maxword;
ramparray[0] [i]:= value;
ramparray[1][i] := value;
ramparray[2][i] := value;
end; 
 
dc:=getdc(0); 
try 
result:= setdevicegammaramp(dc,ramparray) 
finally 
releasedc(0,dc) 
end 
end;
 
 
 
 
 
 
procedure TForm1.Button1Click(Sender: TObject);
begin
setbrightness(64) ; //яркость 
end;
 
 
 
 
 
procedure TForm1.FormCreate(Sender: TObject);
var
  DC: HDC;
begin
  TrackBar1.Max := 255;
  TrackBar1.Position := 128;
  DC := GetDC(0);
    if not GetDeviceGammaRamp(DC, OrigRampArray) then ReleaseDC(0, DC);
end;
 
procedure TForm1.FormClose(Sender: TObject; var Action: TCloseAction);
var
  DC: HDC;
begin
  DC := GetDC(0);
    if not SetDeviceGammaRamp(DC, OrigRampArray) then ReleaseDC(0, DC);
end;