An update to my case, in case it might be helpful to anyone.
After contacting dji support, they suggested to send the unit back to them for inspection.
Before doing so, I thought to try one more time to self-calibrate the sensors.
DJI support suggested that I should perform a low-flight altitude on an area with obstacles and particular something above the aircraft, flying the aircraft on four directions for 2-3 minutes. This did not help at all as it kept detecting false obstacles.
What DID help and fixed the issue was this:
I went to an open area without obstacles (an empty football field) and performed a low altitude flight (2-3m over the ground), flying the Mavic 4 Pro in a cross-like pattern front/back/left/right with obstacle avoidance set to off (not bypass nor brake). The flight was less than 5 minutes (3-4 minutes) and after performing the cross-like flight pattern, I've landed and powered off the aircraft.
This was done 3 times in sequence.
After that, the sensors no longer detect false obstacles, the drone flights fine with either bypass or brake obstacle avoidance action and I can perform automated flights (Mastershots, Waypoints, etc) without issues on the same areas that previously was not possible (in these same areas, the
Mavic 3 can do them without issues).
In any case, that's what I did and now the aircraft is working perfectly.
Hope this helps someone.
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