Possible 3.5.3 issue after sucess PID and only battery change, CRASH

step by step:
1.After succesfull PID tuning (manual) - pitch,roll, althold,loiter- rock solid but battery must change to continue tunning.
2. Landing, checking PID value. roll and pitch 0,2 P value
3. Changing battery
4. checking PID value - increase P on Yaw - (rubber yaw) change 0,3 to 0,32 o P
5. arming and takingoff then copter (8kg X8) behaved like 0 P on roll and pitch like newspaper on strong wind :slight_smile:
6. Crash on his back.

I’ve studying log and found nothing but IMU0 ground mag anomaly
Could someone explainn what could cause this ?

Bin and log


Could someone please check what is wrong. Checking param before and after crash flight and params without significant difference. Uploading FW and setting up from beginning and like described pt.5

After the weekend of searching logs (found nothing - maybe big loops).
Today 23.10 what happen:
-calibrating compass on field ( very good condition)
-takeoff , everything is super, setting up pids (changing by knob in flight-landing saving and then takeoff)
-same thing like last time, end off battery- changing battery
-arming and takingoff then copter like newspaper AND CRASH.

PS. Could be sd card problem ? (it works OK for me - logs, reading,writing)

I have the same problem with two drones (hexacopter). In 3 flights it works perfect but after …the two drones have pixhack 2.1 and here gps. versions 3.5.2 and 3.5.3



Second copter on 3.5.3. Autotune Perfect flight, without problem. New pid saved. Batery change and behave like sets of extra low pids. For sure this is fw issue.