Px4 takeoff motor speed

Hi, I am aware that Px4 is not officially supported by the navio2 platform. I have been successful in running arducopter with my setup before and know that my setup is good because of this, but our team wants to move on to use Px4. I have pushed Px4 to the board and can run all preflight checks just fine. The issue I am having comes on takeoff. This may not even be an issue but what I am experiencing is that on takeoff, as the throttle increases, all motors will spin at higher and higher speeds, like they should, then one of the motors will decide it doesn’t need to spin anymore. This is before the drone even takes off. The hardware is connected properly; motors are in order, spin in the correct direction, and all can get power. When the PIC played with the yaw he could get the “dead” motor to spin again but he didn’t see this as a viable way to take off.

In the lab, with the propellers off, I could replicate the issue and noticed as I played with the yaw the motors that were “dead” would switch. At low throttle, all the motors would spin, but as the throttle increased and the yaw was played with the motor that would not spin would change, sometimes there being two at a time.

I’m thinking this has something to do with a default parameter setting on the motors and likely is an issue with Px4. However, could it be the case that nothing is wrong and as soon as we start to tip the drone on take off the dead motor will wake up and function properly?

Setup Info:
The image I am running on the pi is Linux navio 4.19.83-emlid-v71+ #2 SMP PREEMPT

I also have a video showing the behavior. LMK if this is necessary to show.

This clearly seems like a px4 issue. I think I need to change some system parameters, specifically PWM_MIN for the motor that is initially low. I will post the results.

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Raising the PWM_MIN didn’t fix the issue. There was still a “dead” motor but then the other motors, even at minimum throttle, would still be spinning.