Multiple videos smoothness - threaded playback

Hello! This script only requires a bunch of .mp4s in the data folder. You'll see a collage of 9 videos (or duplicates) in different positions and transparencies. The thing runs ok but even pre-loading the videos at the beginning every time there's a change/swap in one of the videos (around every 4 seconds) the whole thing freezes for a sec, sometimes (try to use mp4s of different sizes).

I tried to use the thread() command in the switching of the videos but nothing happened. I put a println to see the thread but alway show the main thread, I really don't know if I'm doing this ok..

Thanks a LOT for any help!

import processing.video.*;

File path; 
String[] files;
int numfiles = 0;
int timer = -5000;
int tcontrol= 2000;
int numVideos=9;

VideoM[] v = new VideoM[numVideos];
Movie[] vv;

void setup(){
  size(1920, 1080, P2D);
  frameRate(60);
  files = files(); 
  numfiles = files.length;
  if (numfiles>11) numfiles=11;
  loadvideos();

  for(int i = 0;i < numVideos;i++){
     v[i] = new VideoM();
  }
}


void draw() {

  background(0);
  for(int i = 0; i <numVideos; i++){
     v[i].display();
  }

  if ((millis() - timer) > tcontrol)  {
    thread("newvideo");   
    timer = millis();
    tcontrol= int(random(2,6))*1000; 
}
}


void loadvideos(){

 String video;
 vv = new Movie[numfiles];

 for (int i=0; i<numfiles; i++){
   video= files[int(random(numfiles))];
   vv[i] = new Movie(this, video);
   println ("Loading ", video);
 }
}

class VideoM {

 Movie m;
 String video;

 int x;
 int y;
 int w;
 int h;
 int alpha;
 int alphai;
 int fadeout=0;

 VideoM() {
  genera();
  println(numfiles);
  m = vv[int(random(numfiles)) ];
  m.loop();
  // m.volume(random(0.4,0.6));
  // m.speed(random(0.6,1.0));
  m.jump(random(m.duration()));  
  //m.play(); 
 }

 void genera(){
    x=int(random(50, width/2+width/4)); 
    y=int(random(50, height/2+height/4)); 
    w=int(random(280,820));
    h=int(w/1.88);
    alpha=int(random(100,255)); 
    alphai=0; 
 }

 void display(){
   tint(255, alphai);
   if (fadeout==0) {
     alphai++; if (alphai>alpha) alphai=alpha;
   } else {  alphai--; if (alphai<0) {alphai=0;fadeout=0;this.newvid();}
     }

   if (frameCount > 1) { image(m, x, y, w, h); }
 } 

 void cambiavid(){
   fadeout=1;
 }

void newvid() {  
   m=null;
   int j=int(random(numfiles));
   println("cambio: ", j);
   m = vv[j];
   m.loop();
   genera();
   m.jump(random(m.duration())); 
   println(Thread.currentThread());
 }
}  

void newset(){
  for(int i = 0;i < numVideos;i++){
    println(i);
    v[i].newvid();
  }
}

void newvideo(){
  int i = int(random(numVideos));
  //v[i].nuevovid(this);
  v[i].cambiavid();
}

void movieEvent(Movie m) {
  m.read();
}

boolean bStop,bColor=true;
boolean bSave=false,bVidO=false;
void keyPressed()
{
  int k = keyCode;

  // reset all videos
  if (key == 'n' || key == 'N') {
    newset();
    }

}  


// load files in data

String[] files(){
// The data path of the folder to look in (write your own)
java.io.File folder = new java.io.File(dataPath(""));

// let's set a filter (which returns true if file's extension is .jpg)
java.io.FilenameFilter pngFilter = new java.io.FilenameFilter() {
  public boolean accept(File dir, String name) {
    return name.toLowerCase().endsWith(".mp4");
  }
};

// list all the folders inside the main directory
String[] listFolders = folder.list(new java.io.FilenameFilter() {
  public boolean accept(File current, String name) {
    return new File(current, name).isDirectory();
  }
});

// list the files in the data folder, passing the filter as parameter
String[] filenames = folder.list(pngFilter);

return(filenames);
}