Arduplane 3.7.1 Stall / Possible ESC Issue?

Hi! I’ve been facing a strange problem, I think it’s related with the ESC Calibration.

Setup:
Skywalker 1900
Cobra 60A ESC
Turnigy 3548 Motor
Pixhawk 1
10Ah 4S LiPo
I2C Airspeed sensor
Dragonlink v3 Rx/Tx

The Pixhawk is powered by the power module and on the servo rail by the Cobra ESC.

Issue:
Once the motor starts in auto for take off, everything works well, but once the autopilot shuts to zero throttle, it seems that the motor doesn’t start quickly enough, or it stays in zero throttle and the plane starts to stall. I’ve recovered it, changing to FBWA and applying full throttle again.
I’ve attached two logs showing the problem HERE.

After that I’ve changed the servo output for channel 3 on the Taranis from MIN: 950 to 1000 and MAX from 2012 to 2000, did an RC Calibration on MP and an ESC calibration (plugin the ESC Signal cable directly to the Dragon Link Channel 3 Rx) and tried again, things did get better but would highly appreciate if someone could give me another hint on what else to change, look for.

When trying to calibrate the ESC directly connected to the Pixhawk I usually power the Pixhawk through the microUSB port arm in manual and give full throttle, once with full throttle I connect the battery to the power module and wait for the motor beeps and lower the throttle to zero. However, when trying this method, when I connected the microUSB cable to the Pixhawk the motor started to beep as if it had a battery connected, and when arming and giving full throttle the motor started to spin (really slowly btw) but that appears to be really strange so that’s why I did the ESC calibration using the Rx directly, please also let me know what you think about this or if it might be something else wrong.

Thanks!