Unexpected low thrust on Motor 1 & 3 even after cross-swapping FC signal lines – quad tilts forward / then left

Hi everyone,

I’m troubleshooting a X‑config quad running PX4 v1.14 (stable) on a Holybro Pixhawk Mini 6C. The powertrain is BLHeli‑32 35 A ESCs and Emax Eco 2207 2400 KV motors on 4‑cell Li‑Po. Every log shows that Motor 1 and Motor 3 deliver noticeably less thrust than Motor 2 and Motor 4. With the original wiring the aircraft consistently pitches forward on take‑off.

To verify whether the deficit originates in the ESCs/motors or in the flight‑controller outputs, I swapped the PWM signal lines for M1 and M2 at the flight controller(both a ccw). After that change the vehicle began tipping to the left instead of forward, yet the logs still flag “Motor 1” and “Motor 3” as the weak pair and the aircraft start to tilt left.

this is my flight review before switching the pwm signals :

after switching

Has anyone seen this problem before? Thanks for helping