UM6-LT: Euler angles: completely ignore magnetometer

Hello to all,
I bought the UM6-LT a short time ago and use it with an ATmega2560 over the UART. The communication works well, but I have a Problem with the Euler angles and understanding the EKF Variances. Is ist possible to configure the Sensor to don’t consider the magnetometer values, so that I have a yaw value that only contains data of the accelerometer and the gyro? I guess that is possible with the EKF Variances, but I don’t understand what they mean. At the moment the Mag Variance in the CHRobotics Serial Interface is set to 0, the Accel Variance to 5 and the process Variance to 100. If I hold a magnet near to the sensor, the value changes although the Mag Variance is set to 0.
I hope you understood the Problem!
Thank you very much.

Hello, Jan.

The UM6-LT is made by CH Robotics; have you tried contacting them directly? They would probably be able to better help you with your problem.

- Kevin