A problem with the file size

1

I’ve been working on this new cartoon, and was basically done, and just needed to add in some background music. Once I added it in (I don’t know the action script way…I just imported the mp3 into my library and dragged it onto the first frame of the stage), it was fine, and the .swf file size was 341kb I believe. I decided the track wasn’t right for the cartoon, and took it out of the library, and when I did…the .swf was now 3.4 MB!!! I don’t understand why this happened…and it would be nice to bring it back down to the original size. Thanks a lot for your help!