Need help with calibrating ESC's

Hello all,
I’ve got issues calibrating my EMAX 30A ESC’s. I’m running an APM 2.8 with a Turnigy X9 transmitter. When I calibrate directly on the receiver it works perfect using the following order:
Throttle fully up on transmitter + powered on Batt connect Batt disconnect Batt connect Wait for 2 beeps, Throttle fully down Series of beeps, following beeps for 3s LiPo Throttle slightly up,motors spin.
But when I try to do this connected to the APM I get the initial beeps when starting the calibration, but as soon as I hit the throttle down it won’t detect the minimum throttle range. I’ve tried the subtrim, and e-point, but to no avail.
I even went all the way down with the trim to the point it is not recognizing the top position and the ESC’s make the constant beep noise each 0.5 seconds or so, then I kept going slightly up until it recognized the full throttle, but it still won’t recognize the bottom throttle range.
I’ve read that some pixhawk flight controllers have incompatibility issues with EMAX ESC’s and they require 2 components to be desoldered from the ESC’s. I am tempted to attempt this but would like to request some insight here to see if someone has a better solution.
Can anyone please help me?

Also just measured voltages.
On receiver ch3: Low Throttle - 0.18 High Throttle - 0.32
On APM Output 3: Low Throttle - 0.26 High Throttle - 0.46
Is this normal?