V3.1.2 - Throttle signal issue

I have a newly built hexacopter that I am using the Pixhawk in. This is my third self built multi-rotor, and the second using a 3DRobotics FC. I also have a self built deadcat quad with an APM 2.6. Both copters are experiencing similar issues with the upgrade to ArduCopter V3.1.2. The quad flew great prior to the upgrade. After upgrading both to 3.1.2, I recalibrated everything.

When I armed them and gave them throttle, the motors reached a constant speed near the bottom of the travel of the throttle stick and never increased in speed after that. In Mission Planner under the Flight Data/Status Tab I see the following when I move my throttle stick up:

 - Ch3in (Throttle Channel) - Value goes from 1153 to 1867 while throttling up
 - Ch1out through Ch6out (signal to the ESC's) - Value goes from 1151 to only about 1250 right away, then stops and doesn't change at all, no matter what the above input value changes to above around 1250

At about 1/4 throttle travel the output signal maxes out. Any movement of the stick in the upper 3/4 range makes no change to the signal output to the ESCs. The input signal (Ch3in) valuealways moves in proportion to the movement of the throttle stick travel. It seems like there must be some settings within Arducopter that is limiting the max throttle output signal at around 1250. The output signal value varies from channel to channel, usually ranging between around 1254 to 1334.

Both multicopters are using different brand ESC’s and motors. Any help would be appreciated.

Problem was solved by resetting the Pixhawk and reloading the firmware from a cleared Pixhawk.

Resetting was done by doing a load of Ardupilot, then doing the Arducopter load.