Timer interrupts on XIAO

Products & Technology XIAO
9

I think TimerTC3 has a bug.
I tried TimerTc3.initialize 10922 → 10923 and 10923 → 10922 in order.
Then the timer slowed down.

ex.
08:25:40.101 → CountUp:10922
08:25:40.101 → CountUp:10922
08:25:40.135 → CountUp:10922
08:25:40.135 → CountUp:10922
08:25:40.821 → CountUp:10923 <= +686msec
08:25:41.543 → CountUp:10923 <= +722msec
08:25:42.234 → CountUp:10923 <= +691msec

08:41:01.160 → CountUp:10923
08:41:01.160 → CountUp:10923
08:41:01.194 → CountUp:10923
08:41:01.194 → CountUp:10923
08:41:02.605 → CountUp:10922 <= +1.411sec
08:41:04.010 → CountUp:10922 <= +1.405sec
08:41:05.386 → CountUp:10922 <= +1.376sec

Setting from 10922 or less to 10923 or more or from 10923 or more to 10922 or less is NG ?

#include <Arduino.h>
#include <TimerTC3.h>

uint32_t tc_time = 10920;
int  count = 0;

void setup()
{
  Serial.begin(115200);

  while (!Serial) {
    ; // wait for serial port to connect. Needed for native USB port only
  }

  TimerTc3.initialize(tc_time);
  TimerTc3.attachInterrupt(int_timer);
  Serial.println("Start");
}

void loop()
{
  delay(10);
}

void int_timer()
{
  Serial.print("CountUp:");
  Serial.println(tc_time);
  if(++count >= 10)
  {
    tc_time++;
    TimerTc3.stop();
    TimerTc3.initialize(tc_time);
    TimerTc3.attachInterrupt(int_timer);
    count = 0;
  }
}