Strange values for altitude estimation

[simon88]

I'am working with you library with 6 dof captor gyro+accel and one BME280. But I have very strange value for the altitude, my bme captor return to me a value between 287and 288meter but getAltitude()return to me a value between 1460``and 3450` meters. After few minutes altitude block around 3450 and 3460

All values coming from my captor are good m/s for accelerometer and rad/s for gyro and meters for bme and I sent micros() for timestamp