nan values for magnetometer on zed2

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Description

We were using without any trouble the zed2, now we get trouble with the IMU MAG, specifically the magnetometer details

header: 
  seq: 29907
  stamp: 
    secs: 1664573644
    nsecs: 761844325
  frame_id: "zed_mag_link"
magnetic_field: 
  x: nan
  y: nan
  z: nan
magnetic_field_covariance: [3.9e-08, 0.0, 0.0, 0.0, 3.7e-08, 0.0, 0.0, 0.0, 4.7e-08]

We need the raw value to use the madgwick IMU filter to get an absolute value for outdoor navigation.

Steps to Reproduce

Attached a svo simple file to reproduce the case.
Using ROS melodic

zed01.zip

Expected Result

The camera was working fine; from one day to the next week we detected this problem as the outdoor navigation got crazy.

Actual Result

Weird values on IMU and Magnetometer.

ZED Camera model

ZED2

Environment

OS: Ubuntu 18.04.6 LTS
GPU: Nvidia Jetxon Xavier NX and Jetson Nano
Zed SDK: 3.7 and 3.2.1
ROS Melodic

Anything else?

No response

stereolabs / zed-ros2-wrapper

nan values for magnetometer on zed2 #107