Having a sound conflict

Okay, this is what I have in a layer just for scripts, applied to the first frame of this section of my movie:

stop();
introSound.stop(); // Stops the intro music from playing
// This section starts the good trip music at 15% volume and to repeat 99 times
goodSound = new Sound(this);
goodSound.attachSound("Goodtripmusic");
goodSound.setVolume(15);
goodSound.start(0,99);

This is what I have applied to one of my objects in this section of my movie:

on (rollOver) {
guffSound = new Sound(this);
guffSound.attachSound("Guffwav");
guffSound.setVolume(100);
guffSound.start();
}

on (rollOut) {
guffSound.stop();
}

It works perfectly, except for this: the goodSound (ie: Goodtripmusic) plays at 15% volume, as it should. However, my guffSound (ie: Guffwav) also only plays at 15% volume. I thought adding teh setVolume(100) line to the rollOver script would work, but it doesn't.

Anyone understand this conflict?

Thanks for any help!