if (update == 1)
{
    timer++;
    mus_volume(global.currentsong[1], 0, 16);
    if (timer == 16)
        update = 2;
}
if (update == 2)
{
    if (scr_sideb_get_phase() == 2)
    {
        mysong = altsong;
        songspeed = 1.2;
    }
    else
    {
        mysong = defaultsong;
        songspeed = 0.97;
    }
    global.currentsong[0] = snd_init(mysong);
    global.currentsong[1] = mus_loop_ext(global.currentsong[0], 0.8, songspeed);
    update = 0;
    timer = 0;
}