MC messing with my event music

Hey out there;
I just broke up my 16000 frame movie into 12 movieclips and am now laying in the soundtracks and running into problems. Each 12 MCs consist of a page with text and 2 buttons- forward and back.

When it was just one timeline, you could hit the foward and back buttons and the soundtrack would not be affected because it was on Event.

But in the MCs, now when i hit the back button say on MC 5 it restarts the soundtrack.

How do i stop this, and maybe more importantly, why is this happening?

Side note: root timeline consists of 12 frames, each holds a movieclip; on each movieclip page are the forw/back buttons that return the reader to the root timeline, and that triggers the loading of the next movie clip.

A last question just hit me - should i be placing the 3 soundtracks on the root timeline and not in the mc’s themselves?

as always, thanks
Hoss