fixed sound handling bug

src/de/miaurizius/jgame2d/core/GamePanel.java

@@ -30,7 +30,8 @@ public class GamePanel extends JPanel implements Runnable {
     // SYSTEM
     TileManager tileM = new TileManager(this);
     KeyHandler keyH = new KeyHandler();
-    Sound sound = new Sound();
+    Sound se = new Sound();
+    Sound music = new Sound();
     Thread gameThread;
     public CollisionHandler collisionH = new CollisionHandler(this);
     public AssetSetter assetSetter = new AssetSetter(this);;
@@ -102,18 +103,18 @@ public class GamePanel extends JPanel implements Runnable {
     }
 
     public void playMusic(int i) {
-        sound.setFile(i);
-        sound.play();
-        sound.loop();
+        music.setFile(i);
+        music.play();
+        music.loop();
     }
 
     public void stopMusic() {
-        sound.stop();
+        music.stop();
     }
 
     public void playSE(int i) {
-        sound.setFile(i);
-        sound.play();
+        se.setFile(i);
+        se.play();
     }
 
 }