sr = 44100; % the sample rate in Hz
d = 1; % Sound duration in sec
noise = (rand(1, sr*d)*2)-1;

if ispc
    wavplay(noise, sr, 'sync')
    wavplay(noise*10^(-20/20), sr)
elseif ismac
    sound(noise, sr);
    sound(noise*10^(-20/20), sr);
end