Hexacopter entering an uncontrollable yaw spin

I have been having an issue where a hexacopter I built will randomly enter an uncommanded yaw spin. I have encountered this on multiple occasions and have changed the setup. I originally had the hex set up with a Pixhawk 6c and a Holybro Mosaic-H yaw RTK for GPS. however, after failing to correct the yaw spin issue, I switched to a cube orange+ and a here4 GPS, which did not solve the issue. I am leaning towards a desync or a can communication issue with the Hobbywing x6 plus motor/esc combo. I cannot seem to be able to definitively tell from the log whether a desync occurred or whether it may have been a set up issue. Any help would be appreciated!

Log: https://drive.google.com/file/d/1Xsr0tRKt5_guVvNxhkWyVLwJm2kZcxS8/view?usp=sharing

How did you come up wit those Rate Yaw P&I parameter values? Vertical Acceleration Controller gains are at default and the Hover Throttle isn’t. What Tuning Guide are you following?

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I have not seen the log and thus might be wrong, but a common cause is messed up motor orientation / sequencing. try the motor test and see if everything rotates fine and props are on correctly.

As far as I can tell the copter correctly responds to change in yaw, but it is insufficient to counter the spin. I would check if you have any arms or motor mounts that can twist during flight.

A friend gave them to me, but I didn’t really get around to tuning them before it almost crashed due to a yaw spin. I will agree with you that the yaw was not tuned very well.

Well, jacking those parameters to ~7x default makes little sense. I suppose the answer to the question is no tuning guide.

Yaw acts normal most of the time; however, It will randomly enter a yaw spin. I looked at the log more closely and I see a bunch of motor failures. Do you know what that might mean? I am thinking that a desync may be occurring or a CAN bus communication issue.

The motors are fine and the orientation and sequencing is correct because the hex does fly normally. It will enter the yaw spin randomly.