diff --git a/java/libraries/sound/src/processing/sound/MethClaInterface.java b/java/libraries/sound/src/processing/sound/MethClaInterface.java
index bb1a7d4c7..c2c2a6b1c 100644
--- a/java/libraries/sound/src/processing/sound/MethClaInterface.java
+++ b/java/libraries/sound/src/processing/sound/MethClaInterface.java
@@ -7,6 +7,9 @@ public class MethClaInterface
 	  System.loadLibrary("MethClaInterface");
   }
   // Functions I want
+
+  public native int[] mixPlay(int[] input, float[] amp);
+
   
   // Engine