I have posted about a very hard time to get the compass working on big UAVs and in difficult magnetic parts of the planet (Low Magnetic Field region Here2 calibration issues) where I happen to live (Brazil). Before using CUBE Black for our products, I used German Mikrokpter electronics. They have (as does DJI on many of its products) a I2C independent magnetometer board called “External Compass” (http://wiki.mikrokopter.de/en/ExternalCompass). This small independent sensor makes things much easier to be installed in less magnetic crowded parts of the UAV (landing gear as an example). When will you thing of such an option for the CUBE product line?
Hey! You can use Here2 on CAN interface if you feel I2C is a issue for you. If you really need completely independent mag, then https://store.mrobotics.io/product-p/mro10025.htm is the way to go.
There’s always a right place to mount Here2 away from mag field.
This might also happen if you have enabled internal compass and the offsets are too high & inconsistent compared to external one.