SetID of servo CDS5516 with arduino lib

hi,

my CDS5516 servo motor just arrived. It's so cool that we can connect several of them together. so I tried with the library for arduino to set ID of the servos, however it doesnt change anything, could anyone help me to have a look on the code?

===========================
#include <CDS5500.h>

CDS5500 SERVO;

void setup(){
Serial.begin(1000000);//init Serial baudrate
SERVO.SetID(1,2);
}

void loop(){
SERVO.WritePos(2,0x02FF,0x01FF);// Servo ID:1, rotate to the position:0x2FF, rotate speed:0x1FF
delay(1000);
SERVO.WritePos(2,0x0000,0x01FF);// Servo ID:1, rotate to the position:0x000, rotate speed:0x1FF
delay(1000);
}
===================

if I change the ID in the loop() to 1, it runs. means that the SERVO.SetID doesnt work at all...

thank you

cheers