Teensy 3.2 + Adafruit BNO055 IMU + i2c_t3 startup problems

Here is my code:

#include <i2c_t3.h>
#include "Adafruit_BNO055.h"

#define IS_I2C0 true
Adafruit_BNO055 bno = Adafruit_BNO055(IS_I2C0); //Library modified to use i2c_t3

void setup()
{
Serial.begin(115200);
delay(500);
Serial.print("Start...");
Serial.flush();
if (!bno.begin())
Serial.println("Error");
Serial.println("OK");
}

void loop(){}

The result is sometimes (1-5 times in 10):
Start...

instead of:
Start...OK

Changing library i2c_t3 into the standard Wire corrects the problem.