External movieClip loads twice into container MC?

1

Has anyone had this problem? I have a button which loads an external SWF into a container MC on my stage. Every now and then (especially when the system’s resources are taxed) the external movieclip loads twice into the container, and stopping it via the “pause” control only stops the first SWF–the other goes right on playing underneath it.

Here’s my code:

btn01.onRelease = function() {
    container.unloadMovie();
    myMCL.loadClip("assets/01.swf",container);
}

Unloading the container before loading in a new SWF made the duplication happen less often, but it still happens now and then. Does anyone have any idea what might be going on here?

Thank you in advance for your help. I’ll be presenting this project tomorrow!