Need help with sound looping!

So I finally figured out how to properly script my buttons for the different sounds and sound effects that I want, but now I ran into a new problem.

I am going to have 8 different background loops that you can choose from, but since I am using actionscript to control the sounds, I dont know how to make them loop. Here is the code I have so far.

check1 = new string("false");
check2 = new string("false");

bt1 = new Sound();
bt1.attachSound("beat_1");
bt2 = new Sound();
bt2.attachSound("beat_2");

beat1.onRelease = function() {

if (check1 == "false")
{
bt1.start();
check1 = "true";
}

else
{
bt1.stop("beat_1");
check1 = "false";
}
};

beat2.onRelease = function() {
if (check2 == "false")
{
bt2.start();
check2 = "true";
}

else
{
bt2.stop("beat_2");
check2 = "false";
}
};


The sounds are only about 5 second loops. How do I get them to loop continously?

nevermind..... I got it figured out! Now im havin a new problem though