     }
     else if(diff != 0.0){
       effect_brightness = effect_brightness_target;
+      updateLED();
     }
   }
 }

  else {

    // instrument brightness
    if(instrument_brightness_min+0.01 <= instrument_brightness) {
      instrument_brightness -= 0.01;
      updateLED();
    }

    // effect brightness
    // fade effect brightness to effect_brightness_target value
    float diff = abs(effect_brightness_target-effect_brightness);
    if(0.01<diff){

      // Serial.println(instrument_brightness_min);
      updateLED();
    }
    // set instrument_brightness_target value
    // "b:[0.0-1.0];"
    else if(command=="B") {
      // TODO argument check
      // argument is float
      instrument_brightness_target = argument.toFloat();
      // Serial.print("set instrument_brightness min value: ");
      // Serial.println(instrument_brightness_target);
      updateLED();
    }
    else {
      Serial.print("Command not found: ");
      Serial.println(command);
