Vibration Tutorial Help

Hi,

There is a vibration tutorial on here. I am having trouble making two objects vibrate at once. One movieclip always trumps the other.

The vibration works, but the duplication doesnt

for (var i = 0; i<35; i++) {
circle4.duplicateMovieClip(i, i);
}

i tried putting two of that and then i tried this

for (var i = 0; i<35; i++) {
circle4.duplicateMovieClip(i, i);
circle6.duplicateMovieClip(i, i);
}

any help would be great.

thanks!