Keyboard Tray V2 with Arduino

So I made a Keyboard try a few weeks ago, but was not happy with the way it turned out.  There were a few things that I found that I wanted to add.  So this is the next version, added two CAC readers and an audio switcher to be able to choose from headphones or speakers. There is a USB hub inside the tray that powers the three items and an Arduino.  The Arduino is used to power and control the lights on the top..

I have attached the code for the Arduino below.

// Blink 8 sets of 4 LEDs per circut at a random interval (1 second to 2.5 seconds) without using delay()
//Curcuit:  LEDs connected to pin 13-6, all with 330 ohm resistors to ground.

int led1Pin =  13;
int led2Pin = 12;
int led3Pin = 11;
int led4Pin = 10;
int led5Pin = 9;
int led6Pin = 8;
int led7Pin = 7;
int led8Pin = 6;

int led1State = LOW;
int led2State = LOW;
int led3State = LOW;
int led4State = LOW;
int led5State = LOW;
int led6State = LOW;
int led7State = LOW;
int led8State = LOW;

long previousMillis1 = 0;
long previousMillis2 = 0;
long previousMillis3 = 0;
long previousMillis4 = 0;
long previousMillis5 = 0;
long previousMillis6 = 0;
long previousMillis7 = 0;
long previousMillis8 = 0;
long randInterval1 = 0;
long randInterval2 = 0;
long randInterval3 = 0;
long randInterval4 = 0;
long randInterval5 = 0;
long randInterval6 = 0;
long randInterval7 = 0;
long randInterval8 = 0;

void setup() {

  pinMode(led1Pin, OUTPUT);
  pinMode(led2Pin, OUTPUT);
  pinMode(led3Pin, OUTPUT);
  pinMode(led4Pin, OUTPUT);
  pinMode(led5Pin, OUTPUT);
  pinMode(led6Pin, OUTPUT);
  pinMode(led7Pin, OUTPUT);
  pinMode(led8Pin, OUTPUT);

  randomSeed (analogRead (0));
}

void loop()
{
  unsigned long currentMillis = millis();


//LED 1/////////////////////////
  if(currentMillis – previousMillis1 > randInterval1) {
    randInterval1 = random (1000, 2500);
    previousMillis1 = currentMillis;  
   
    if (led1State == LOW)
      led1State = HIGH;
    else
      led1State = LOW;

    digitalWrite(led1Pin, led1State);
  }

//LED 2/////////////////////////
    if(currentMillis – previousMillis2 > randInterval2) {
    randInterval2 = random (1000, 2500);
    previousMillis2 = currentMillis;  

    if (led2State == LOW)
      led2State = HIGH;
    else
      led2State = LOW;

    digitalWrite(led2Pin, led2State);
  }

//LED 3/////////////////////////
      if(currentMillis – previousMillis3 > randInterval3) {
    randInterval3 = random (1000, 2500);
    previousMillis3 = currentMillis;  

    if (led3State == LOW)
      led3State = HIGH;
    else
      led3State = LOW;

    digitalWrite(led3Pin, led3State);
  }


//LED 4/////////////////////////

        if(currentMillis – previousMillis4 > randInterval4) {
    randInterval4 = random (1000, 2500);
    previousMillis4 = currentMillis;  

    if (led4State == LOW)
      led4State = HIGH;
    else
      led4State = LOW;

    digitalWrite(led4Pin, led4State);
  }

//LED 5/////////////////////////

         if(currentMillis – previousMillis5 > randInterval5) {
    randInterval5 = random (1000, 2500);
    previousMillis5 = currentMillis;  

    if (led5State == LOW)
      led5State = HIGH;
    else
      led5State = LOW;

    digitalWrite(led5Pin, led5State);
  }

//LED 6/////////////////////////

         if(currentMillis – previousMillis6 > randInterval6) {
    randInterval6 = random (1000, 2500);
    previousMillis6 = currentMillis;  

    if (led6State == LOW)
      led6State = HIGH;
    else
      led6State = LOW;

    digitalWrite(led6Pin, led6State);
  }

//LED 7/////////////////////////

         if(currentMillis – previousMillis7 > randInterval7) {
    randInterval7 = random (1000, 2500);
    previousMillis7 = currentMillis;  

    if (led7State == LOW)
      led7State = HIGH;
    else
      led7State = LOW;

    digitalWrite(led7Pin, led7State);
  }

//LED 8/////////////////////////

         if(currentMillis – previousMillis8 > randInterval8) {
    randInterval8 = random (1000, 2500);
    previousMillis8 = currentMillis;  

    if (led8State == LOW)
      led8State = HIGH;
    else
      led8State = LOW;

    digitalWrite(led8Pin, led8State);
  }