[<<D>>]

Ладно, вот я написал полный кодинг проги:

unit Unit1;

interface

uses
Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
Dialogs,MMSystem, MPlayer;

const
MCI_SETAUDIO = $0873;
MCI_DGV_SETAUDIO_VOLUME = $4002;
MCI_DGV_SETAUDIO_ITEM = $00800000;
MCI_DGV_SETAUDIO_VALUE = $01000000;
MCI_DGV_STATUS_VOLUME = $4019;
WM_MYICONNOTIFY = WM_USER + 123;

type
MCI_DGV_SETAUDIO_PARMS = record
dwCallback: DWORD;
dwItem: DWORD;
dwValue: DWORD;
dwOver: DWORD;
lpstrAlgorithm: PChar;
lpstrQuality: PChar;
end;

var
MciOpenParams :MCI_OPEN_PARMS;
MciSetParams :Mci_Set_Parms;
MciStatusParams :MCI_Status_PARMS;
MciPlayParams :Mci_Play_Parms;
MCIWindowParams :TMCI_Anim_Window_Parms;
MciRectParams :MCI_ANIM_RECT_PARMS;
MciSeekParams :Mci_Seek_Parms;

type
TForm1 = class(TForm)
mp: TMediaPlayer;
OpenDialog1: TOpenDialog;
procedure FormCreate(Sender: TObject);
private
{ Private declarations }
public
{ Public declarations }
end;

var
Form1: TForm1;

implementation

procedure SetMPVolume(DeviceID:word; Volume: Integer);
{ Volume: 0 - 1000 }
var
p: MCI_DGV_SETAUDIO_PARMS;
begin
{ Volume: 0 - 1000 }
p.dwCallback := 0;
p.dwItem := MCI_DGV_SETAUDIO_VOLUME;
p.dwValue := Volume;
p.dwOver := 0;
p.lpstrAlgorithm := nil;
p.lpstrQuality := nil;
mciSendCommand(DeviceID, MCI_SETAUDIO,
MCI_DGV_SETAUDIO_VALUE or MCI_DGV_SETAUDIO_ITEM, Cardinal(@p));
end;

{$R *.dfm}

procedure TForm1.FormCreate(Sender: TObject);
begin
if opendialog1.execurte then
begin
mp.FileName:=opendialog1.FileName;
mp.Open;
mp.Play;
setmpvolume(mp.DeviceID,0);
end;
end;

end.