Solves "Synchronization on a non-final field 'audioLock'" (#46)

Solves "Synchronization on a non-final field 'audioLock'"

Author: goxr3plus

src/main/java/com/goxr3plus/streamplayer/stream/StreamPlayer.java

@@ -84,7 +84,7 @@ public class StreamPlayer implements StreamPlayerInterface, Callable<Void> {
 	/**
 	 * It is used for synchronization in place of audioInputStream
 	 */
-	private volatile Object audioLock = new Object();
+	private final Object audioLock = new Object();
 
 	// -------------------VARIABLES---------------------