diff --git a/assets/js/components/calls/callWindow.js b/assets/js/components/calls/callWindow.js
index 51c7fca7..4b40ea66 100644
--- a/assets/js/components/calls/callWindow.js
+++ b/assets/js/components/calls/callWindow.js
@@ -694,7 +694,7 @@ ComunicWeb.components.calls.callWindow = {
 			call.signalClient.sendSignal(member.user_call_id, JSON.stringify(data));
 		});
 
-		peer.on("message", message => {
+		peer.on("message", function(message){
 			console.log("Message from remote peer: " + message);
 		});
 
@@ -788,7 +788,7 @@ ComunicWeb.components.calls.callWindow = {
 		/**
 		 * @type {HTMLVideoElement}
 		 */
-		let video = createElem2({
+		var video = createElem2({
 			appendTo: call.window.videosTarget,
 			type: "video"
 		});
diff --git a/assets/js/components/calls/controller.js b/assets/js/components/calls/controller.js
index 91a40f86..8ac9477a 100644
--- a/assets/js/components/calls/controller.js
+++ b/assets/js/components/calls/controller.js
@@ -94,7 +94,7 @@ ComunicWeb.components.calls.controller = {
 	 * 
 	 * @return Cached calls configuration
 	 */
-	getConfig() {
+	getConfig: function() {
 		return ComunicWeb.components.calls.__config;
 	},
 
diff --git a/assets/js/components/calls/currentList.js b/assets/js/components/calls/currentList.js
index 483cbd5a..9f4863a4 100644
--- a/assets/js/components/calls/currentList.js
+++ b/assets/js/components/calls/currentList.js
@@ -42,7 +42,7 @@ ComunicWeb.components.calls.currentList = {
 	 * @param {number} id The ID of the call to add
 	 */
 	addCallToList: function(id){
-		let list = this.getCurrentCallsList();
+		var list = this.getCurrentCallsList();
 
 		if(!list.includes(""+id))
 			list.push(id);
@@ -57,7 +57,7 @@ ComunicWeb.components.calls.currentList = {
 	 */
 	removeCallFromList: function(id){
 
-		let list = this.getCurrentCallsList();
+		var list = this.getCurrentCallsList();
 
 		while(list.includes(""+id))
 			list.splice(list.indexOf(""+id), 1);
diff --git a/assets/js/components/conversations/chatWindows.js b/assets/js/components/conversations/chatWindows.js
index c4494620..37b183dc 100644
--- a/assets/js/components/conversations/chatWindows.js
+++ b/assets/js/components/conversations/chatWindows.js
@@ -586,7 +586,7 @@ ComunicWeb.components.conversations.chatWindows = {
 			//for conversation of two people
 
 		//Add the call button
-		let button = createElem2({
+		var button = createElem2({
 			insertBefore: conversation.box.boxTools.firstChild,
 			type: "button",
 			class: "btn btn-box-tool",
diff --git a/builder b/builder
index c03af7bc..402eb058 100755
--- a/builder
+++ b/builder
@@ -63,11 +63,12 @@ function files_to_file(array $files, string $target) : bool {
 /**
  * Copy an array of files into a specific target file using uglifyJS
  * 
+ * @param string $begin_path The begining of each path
  * @param array $files The name of the source file
  * @param string $target The target file
  * @return bool TRUE in case of success / FALSE in case of failure
  */
-function js_files_to_file(array $files, string $target){
+function js_files_to_file(string $begin_path, array $files, string $target){
 
 	$source = "";
 
@@ -77,17 +78,46 @@ function js_files_to_file(array $files, string $target){
 
 	foreach($files as $file){
 
-		//Compress file
-		notice("Parsing with UGLIFYJS: ".$file);
-		exec("/usr/bin/uglifyjs '".$file."' -c -o ".TEMP_FILE, $output, $exit_code);
-		
-		//Get the content of the file
-		$source .= "\n".file_get_contents(TEMP_FILE);
+		$uglifyjs = true;
 
-		if($exit_code != 0){
-			notice("An error (".$exit_code.") occured while parsing file ".$file, TRUE);
-			exit(10);
+		//Check if file entry is an array or a string
+		if(is_string($file))
+			$file = $begin_path.$file;
+
+		//It is an array
+		else if(is_array($file)) {
+
+			//Check if we have special information for uglifyjs
+			if(isset($file["uglifyjs"]))
+				$uglifyjs = $file["uglifyjs"];
+			
+			$file = $begin_path.$file["path"];
 		}
+
+		//Else the kind of entry is not supported
+		else
+			throw new Exception("Excepted string or array, got something else for javascript entry!");
+
+		//Compress file
+		if($uglifyjs){
+			notice("Parsing with UGLIFYJS: ".$file);
+			exec("/usr/bin/uglifyjs '".$file."' -c -o ".TEMP_FILE, $output, $exit_code);
+
+			//Get the content of the file
+			$source .= "\n".file_get_contents(TEMP_FILE);
+
+			if($exit_code != 0){
+				notice("An error (".$exit_code.") occured while parsing file ".$file, TRUE);
+				exit(10);
+			}
+
+		}
+
+		//Else we take the file as is
+		else 
+			$source .= "\n".file_get_contents($file);
+	
+		
 	}
 
 	//Delete the temp file
@@ -192,9 +222,8 @@ files_to_file($thirdPartyDebugFiles, $targetThirdPartyCSS);
 
 //3rd party JS
 notice("Third Party JS");
-$thirdPartyDebugFiles = array_put_begining($path_debug_assets, $debug::THIRD_PARTY_JS);
 $targetThirdPartyJS = $path_release_assets.$release::THIRD_PARTY_JS;
-js_files_to_file($thirdPartyDebugFiles, $targetThirdPartyJS);
+js_files_to_file($path_debug_assets, $debug::THIRD_PARTY_JS, $targetThirdPartyJS);
 
 //App CSS
 notice("App CSS");
@@ -204,9 +233,8 @@ files_to_file($appDebugFiles, $targetAppCSS);
 
 //App JS
 notice("App JS");
-$appDebugFiles = array_put_begining($path_debug_assets, $debug::APP_JS);
 $targetAppJS = $path_release_assets.$release::APP_JS;
-js_files_to_file($appDebugFiles, $targetAppJS);
+js_files_to_file($path_debug_assets, $debug::APP_JS, $targetAppJS);
 
 
 //Make some adpations on third party files
@@ -231,6 +259,8 @@ rcopy($path_debug_assets."3rdparty/adminLTE/plugins/iCheck/flat/icheck-flat-imgs
 rcopy($path_debug_assets."img/", $path_release_assets."img/");
 rcopy($path_debug_assets."templates/", $path_release_assets."templates/");
 
+//Copy songs
+rcopy($path_debug_assets."audio/", $path_release_assets."audio/");
 
 //Copy dark theme
 rcopy($path_debug_assets."css/dark_theme.css", $path_release_assets."css/dark_theme.css");
diff --git a/system/config/dev.config.php b/system/config/dev.config.php
index a208003a..a2cb329d 100644
--- a/system/config/dev.config.php
+++ b/system/config/dev.config.php
@@ -161,8 +161,8 @@ class Dev {
 		"3rdparty/js-bbcode-parser/bbcode-parser.js",
 
 		//Simple peer
-		"3rdparty/simplepeer/simplepeer.min.js",
-		"3rdparty/SignalExchangerClient/SignalExchangerClient.js"
+		array("path" => "3rdparty/simplepeer/simplepeer.min.js", "uglifyjs" => false),
+		array("path" => "3rdparty/SignalExchangerClient/SignalExchangerClient.js", "uglifyjs" => false)
 	);
 
 	/**
@@ -320,7 +320,7 @@ class Dev {
 		"js/common/formChecker.js",
 		"js/common/date.js",
 		"js/common/system.js",
-		"js/common/songPlayer.js",
+		array("path" => "js/common/songPlayer.js", "uglifyjs" => false),
 
 		//Languages
 		"js/langs/en.inc.js",
diff --git a/system/system.php b/system/system.php
index a2666115..c399d3db 100644
--- a/system/system.php
+++ b/system/system.php
@@ -134,6 +134,10 @@ function src_inc_list_js(string $assets_url, array $files) : string {
 
     //Process the list of files
     foreach($files as $file){
+
+        if(is_array($file))
+            $file = $file["path"];
+
         $source .= src_inc_js($assets_url.$file)."\n\t\t";
     }