Problem controlling multiple sounds

[fr4nck]

Hi, first of all, sorry if my english may be bad,

I have problems controlling multiple sounds over multiple movieclip:

My sounds are declared on the roots:

guitareSon1 = new Sound(volSlider1);
guitareSon2 = new Sound(volSlider2);
basseSon = new Sound(volSlider3);
batterieSon = new Sound(volSlider4);
saxSon = new Sound(volSlider5);
tamtamSon = new Sound(volSlider6);

Sounds are attached in another movieclip, in a button: here is an example:

on (release){
    _root.guitareSon1.attachSound("sonGuitA0");
}

And finally sounds are controlled in another movieclip, each sounds are controlled separatly:
here is the code of one slider, that is supposed to control only the "guitareSon1", but my problem is that the slider control all the sounds simultaneously

onClipEvent (load) {
    _parent.volSlider1.drag._x += 50;
}
onClipEvent (enterFrame) {
    vol = _parent.volSlider1.drag._x+50;
    _root.guitareSon1.setVolume(vol);
    _parent.volAt = Math.round(vol);
}

My problem is that the slider control all the sounds simultaneously... everything seem to work fine if the whole code and objects are on the root, but i really need to control this over multiple movieclip!

Anyone can help?

Thanks