Audio WILL continue to play on unloaded movie clips. Believe it or not, this is actually documented in the Loader class. Check this out:
As a best practice, before you unload a child SWF file, you should explicitly close any streams in the child SWF file's objects, such as LocalConnection, NetConnection, NetStream, and Sound objects. Otherwise, audio in the child SWF file might continue to play, even though the child SWF file was unloaded. To close streams in the child SWF file, add an event listener to the child that listens for the unload event. When the parent calls Loader.unload(), the unload event is dispatched to the child. The following code shows how you might do this:
function closeAllStreams(evt:Event) {
myNetStream.close();
mySound.close();
myNetConnection.close();
myLocalConnection.close();
}
However, there's actually even more to it than that. If you are truly intending to unload the clip so that garbage collection may occur, you also need to remove any (and all) event listeners that would have a reference to the Loader or to its children (the contentLoaderInfo object, for instance). So make sure that you also mLoader.contentLoaderInfo.removeEventListener() for your COMPLETE and PROGRESS events as well, before running the unload() method.
Best,
Tom
