loading bar problem for multiple sounds loaded

Hello. I am loading multiple mp3 sounds with a loading bar. they load fine, but the problem is that during loading the bar does not advance and only advances at full speed at the end (as if it only works with the last sound) I have tried putting large files and the same thing happens, it takes longer to load and only you see the bar at the end at full speed. (barely visible).

Thanks for the help. this is the code

public class Standars_all_mc extends MovieClip {


		private var sound0:Sound = new Sound();
		private var sound1:Sound = new Sound();
		private var sound2:Sound = new Sound();
		private var sound3:Sound = new Sound();
		private var sound4:Sound = new Sound();
		private var sound5:Sound = new Sound();
		private var sound6:Sound = new Sound();
		private var sound7:Sound = new Sound();
		private var sound8:Sound = new Sound();
		private var sound9:Sound = new Sound();
		private var sound10:Sound = new Sound();
		private var sound11:Sound = new Sound();
		private var sound12:Sound = new Sound();
etc...................
		
		private var soundA:Array = ["sound0","sound1","sound2"];
		private var soundB:Array = ["sound3","sound4","sound5"];
etc.........................
		
		private var soundZ:Array = ["sound0","sound1","sound2","sound3","sound4","sound5","sound6","sound7","sound8","sound9","sound10","sound11","sound12","sound13","sound14","sound15","sound16","sound17","sound18","sound19","sound20","sound21","sound22","sound23","sound24","sound25","sound26","sound27","sound28","sound29","sound30","sound31","sound32","sound33","sound34","sound35","sound36","sound37","sound38","sound39","sound40","sound41","sound42","sound43","sound44","sound45","sound46","sound47","sound48","sound49","sound50","sound51","sound52","sound53"];

		private var i:int;
		//soundA
		var Bergamasca0:String = "https://drive.google.com/uc?id=1Y36t7fLgRHqQ4XLZajC5VHSYuhLM1FKV&export=download";
		var Bergamasca1:String = "https://drive.google.com/uc?id=1P4WDhtAm3XCnG1wcNObCKXFy00wE83Vz&export=download";
		var Bergamasca2:String = "https://drive.google.com/uc?id=1ihNAVa82jGkr973tfpre1wf3zdT3kPR1&export=download";
		//soundB
		var Bergamasca3:String = "https://drive.google.com/uc?id=1IDv5pTbh94GT_dqocQuSZqfQH1CtysNR&export=download";
		var Bergamasca4:String = "https://drive.google.com/uc?id=1MKkj30XSC_Is-jWYKqnb2KVVIBZqa0Kg&export=download";
		var Bergamasca5:String = "https://drive.google.com/uc?id=1eOzms1xf_Do0FSYmNciC1gSnG2I5Oh0A&export=download";
		//soundC
		var Bergamasca6:String = "https://drive.google.com/uc?id=1r4z6r4dw0Yv3Ljuxm4Qomx6IsQHC2Flv&export=download";
		var Bergamasca7:String = "https://drive.google.com/uc?id=145j8Vj8H7Z1fUuD5g03-KlwyAe7RN2Wy&export=download";
		var Bergamasca8:String = "https://drive.google.com/uc?id=16zGvRdTK6fvzBM3PmYrKSXKtQFQC6saD&export=download";
		//soundD
etc................................
		
		public function Standars_all_mc() {
			this.addEventListener(Event.ADDED_TO_STAGE,addedF);
		}
		
		private function addedF(e:Event):void{
			//if(!back_mc.hasEventListener(MouseEvent.MOUSE_DOWN)){
					
			load_soundsF();
			}
//carga de sonidos
		
		private function load_soundsF():void {
			
			//bar
			controlCarga.width = 320;
			controlCarga.height = 7;
			addChild (controlCarga);
			controlCarga.move((width/2)-320,height/2);
			pantallaCarga.gotoAndStop(2);

			//sounds charge
			for (var i:uint=0; i<54; i++) {
				this[soundZ[i]] = new Sound();
				this[soundZ[i]].load (new URLRequest(this[Data.so.data.sound+i]));
				controlCarga.source = this[soundZ[i]];
				controlCarga.addEventListener(ProgressEvent.PROGRESS, imagenProgreso);
				controlCarga.addEventListener(IOErrorEvent.IO_ERROR, onError);
				controlCarga.addEventListener(Event.COMPLETE, imagenCargada);
			}
			function imagenProgreso(event:ProgressEvent):void {
				//pantallaCarga.formato_1.text = "Cargando" + Data.so.data["sound"].split("_").join(" ")+".......";
				//"Load..." + Math.floor(event.bytesLoaded / 1024) + "/" + Math.floor(event.bytesTotal / 1024) + "KB";
				//trace("progressHandler: bytesLoaded=" + e.bytesLoaded + " bytesTotal=" + e.bytesTotal);
			}

			function imagenCargada(event:Event):void {
				pantallaCarga.formato_1.text = Data.so.data["sound"].split("_").join(" ")+" cargado con exito";
				pantallaCarga.gotoAndPlay(3);

				if (contains (controlCarga)){
					removeChild (controlCarga);
				}
			}

			function onError(event:IOErrorEvent):void {
				trace("ioErrorHandler");
				//pantallaCarga.play();
				dispatchEvent(backE);
			}
		}