Does your 1.swf use any _root references in the code? If so, you may need to use this._lockroot = true; in frame 1 of the main timeline of the 1.swf file.
The only root reference to the Main.FLA that I have are to change variables that are defined in the Main.FLA. I've added the code you suggested to the 1st frame in 1.SWF and the sound still doesn't play.
Do you load the file into the main using code?
Yes, in my Main.FLA, I have a link/button with the following code:
var myMCL = new MovieClipLoader();
myMCL.onLoadComplete = function(targetMC)
//this code removes a message, "Content Loading... Please wait."
Chp3.swf (which I just renamed in these threads to 1.SWF) loads just fine and everything in it functions just fine, even the reporting of variable values to the Main.FLA, except that the sound does not play.
I still haven't been able to figure out this problem? Any ideas as to why this is happening?
I found some information on-line that helped me figure out how to fix this issue. First, I moved the sound object code to the timeline of the movieclip in which I wanted to play the sound, even if the movieclip was in a loaded SWF. So if I my sound should play in mc_1.mc_2.mc_3, the sound object is created in mc_3 timeline. Also, when creating the sound object, "this" is placed as the parameter, as such:
soundObject = new Sound(this);
Also, when stoping the sound, I'm using stopAllSounds() instead of soundObject.stop().
I hope this helps someone who is struggling with this same issue.