I am trying to play this midi song.

But the tempo is all wrong.

I am simply doing:

        MIDI.loadPlugin({
            soundFontUrl: "./soundfont/",
            onsuccess: function(){
                console.log('loaded');
                MIDI.Player.loadFile("data:audio/midi;base64,"+song, function(){
                    console.log('here');
                    MIDI.Player.start();
                }
                );
            },
        });

I posted the song variable I used here (it was too large for StackOverflow).

Any ideas?