Description

This method changes windows sound volume with waveOutSetVolume API method

Delphi code

type
    tvolRange=1..15;
Procedure ChangeVolume(value:tvolRange);
var
    Count, i: integer;
begin
    Count := waveOutGetNumDevs;
    for i := 0 to Count do
    begin
        waveOutSetVolume(i,longint(value*4369)*65536+longint(value*4369));
    end;
end;