Guru Meditation Error: Core  1 panic'ed (Interrupt wdt timeout on CPU1)

Legyártottam a kód inkriminált részét. Pont ugyan azt teszi amit a sajátom.
Nem akartam széjjel tutujgatni a sajátomat.

#include <FastLED.h>

#define LED_PIN     2
#define NUM_LEDS    60
#define BRIGHTNESS  255
#define LED_TYPE    WS2812B
#define COLOR_ORDER GRB
CRGB leds[NUM_LEDS];

void IRAM_ATTR onTimer(){   //körbe forgatja a ledek tartalmát

            leds[59] = leds[40];
            leds[39] = leds[20];
            leds[19] = leds[0];


        for(int dot = 0; dot < 20; dot++) {
            leds[dot+40] = leds[dot+41];
            leds[dot+20] = leds[dot+21];
            leds[dot] = leds[dot+1];
            FastLED.show();     //megjeleníti.

}
}

void setup() {
  hw_timer_t * timer = NULL;

  // put your setup code here, to run once:
  /* Use 1st timer of 4 */
  /* 1 tick take 1/(80MHZ/80) = 1us so we set divider 80 and count up */
  timer = timerBegin(0, 80, true);

  /* Attach onTimer function to our timer */
  timerAttachInterrupt(timer, &onTimer, true);

  /* Set alarm to call onTimer function every second 1 tick is 1us
  => 1 second is 1000000us */
  /* Repeat the alarm (third parameter) */
  timerAlarmWrite(timer, 5000, true);   //100Hz

  /* Start an alarm */
  timerAlarmEnable(timer);

  FastLED.addLeds<LED_TYPE, LED_PIN, COLOR_ORDER>(leds, NUM_LEDS).setCorrection( TypicalLEDStrip );
  FastLED.setBrightness(  BRIGHTNESS );

for (int dot=0;dot <= 10; dot ++) { //sárga és fekete szineket állít be.
      leds[dot] = CRGB::Orange;
      leds[dot+10] = CRGB::Black;
      leds[dot+20] = CRGB::Orange;
      leds[dot+30] = CRGB::Black;
      leds[dot+40] = CRGB::Orange;
      leds[dot+50] = CRGB::Black;
    }


}

void loop() {
  // put your main code here, to run repeatedly:

}