I would guess that the IR-leds aren't hitting the hole surface.      

I haven't even written any code I'm just using the example for the TUIO Client library. Here it is anyway

 

import TUIO.*;
TuioProcessing tuioClient;

// these are some helper variables which are used
// to create scalable graphical feedback
float cursor_size = 15;
float object_size = 60;
float table_size = 760;
float scale_factor = 1;
PFont font;

void setup()
{
  //size(screen.width,screen.height);
  size(640,480);
  noStroke();
  fill(0);
 
  loop();
  frameRate(30);
  //noLoop();
 
  hint(ENABLE_NATIVE_FONTS);
  font = createFont("Arial", 18);
  scale_factor = height/table_size;
 
  // we create an instance of the TuioProcessing client
  // since we add "this" class as an argument the TuioProcessing class expects
  // an implementation of the TUIO callback methods (see below)
  tuioClient  = new TuioProcessing(this);
}

// within the draw method we retrieve a Vector (List) of TuioObject and TuioCursor (polling)
// from the TuioProcessing client and then loop over both lists to draw the graphical feedback.
void draw()
{
  background(255);
  textFont(font,18*scale_factor);
  float obj_size = object_size*scale_factor;
  float cur_size = cursor_size*scale_factor;
  
  Vector tuioObjectList = tuioClient.getTuioObjects();
  for (int i=0;i<tuioObjectList.size();i++) {
     TuioObject tobj = (TuioObject)tuioObjectList.elementAt(i);
     stroke(0);
     fill(0);
     pushMatrix();
     translate(tobj.getScreenX(width),tobj.getScreenY(height));
     rotate(tobj.getAngle());
     rect(-obj_size/2,-obj_size/2,obj_size,obj_size);
     popMatrix();
     fill(255);
     text(""+tobj.getSymbolID(), tobj.getScreenX(width), tobj.getScreenY(height));
   }
  
   Vector tuioCursorList = tuioClient.getTuioCursors();
   for (int i=0;i<tuioCursorList.size();i++) {
      TuioCursor tcur = (TuioCursor)tuioCursorList.elementAt(i);
      Vector pointList = tcur.getPath();
     
      if (pointList.size()>0) {
        stroke(0,0,255);
        TuioPoint start_point = (TuioPoint)pointList.firstElement();;
        for (int j=0;j<pointList.size();j++) {
           TuioPoint end_point = (TuioPoint)pointList.elementAt(j);
           line(start_point.getScreenX(width),start_point.getScreenY(height),end_point.getScreenX(width),end_point.getScreenY(height));
           start_point = end_point;
        }
       
        stroke(192,192,192);
        fill(192,192,192);
        ellipse( tcur.getScreenX(width), tcur.getScreenY(height),cur_size,cur_size);
        fill(0);
        text(""+ tcur.getCursorID(),  tcur.getScreenX(width)-5,  tcur.getScreenY(height)+5);
      }
   }
  
}

// these callback methods are called whenever a TUIO event occurs

// called when an object is added to the scene
void addTuioObject(TuioObject tobj) {
  println("add object "+tobj.getSymbolID()+" ("+tobj.getSessionID()+") "+tobj.getX()+" "+tobj.getY()+" "+tobj.getAngle());
}

// called when an object is removed from the scene
void removeTuioObject(TuioObject tobj) {
  println("remove object "+tobj.getSymbolID()+" ("+tobj.getSessionID()+")");
}

// called when an object is moved
void updateTuioObject (TuioObject tobj) {
  println("update object "+tobj.getSymbolID()+" ("+tobj.getSessionID()+") "+tobj.getX()+" "+tobj.getY()+" "+tobj.getAngle()
          +" "+tobj.getMotionSpeed()+" "+tobj.getRotationSpeed()+" "+tobj.getMotionAccel()+" "+tobj.getRotationAccel());
}

// called when a cursor is added to the scene
void addTuioCursor(TuioCursor tcur) {
  println("add cursor "+tcur.getCursorID()+" ("+tcur.getSessionID()+ ") " +tcur.getX()+" "+tcur.getY());
}

// called when a cursor is moved
void updateTuioCursor (TuioCursor tcur) {
  println("update cursor "+tcur.getCursorID()+" ("+tcur.getSessionID()+ ") " +tcur.getX()+" "+tcur.getY()
          +" "+tcur.getMotionSpeed()+" "+tcur.getMotionAccel());
}

// called when a cursor is removed from the scene
void removeTuioCursor(TuioCursor tcur) {
  println("remove cursor "+tcur.getCursorID()+" ("+tcur.getSessionID()+")");
}

// called after each message bundle
// representing the end of an image frame
void refresh(TuioTime bundleTime) {
  redraw();
}