Multiple sound files in Flash timeline

I’m having a little issue with the sound on my flash website. The way my site is set up so far is that after the preloader, i have an enter site page that holds there until the user clicks on the “enter site” button. Once they click that button it takes them to the site. I would like to add 2 different sound files to this. One file for the enter site that loops over and over until the user enters the site and then that sound file will stop and the other sound file will start. When I tried this I could not get the first sound file to quit playing once you enter the site. So basically when I am on the “enter page” it’s playing the looping file fine but when I click “enter site” it plays the other audio file on top of the one looping. I hope this makes sense. Can someone tell me what I should do. Thanks in advance!