Copter descending slowly, landing, tip-over during Auto mission

All,

I would really appreciate any help with my issue. My copter is descending sporadically during an auto mission. It will lose so much altitude that it crashes slowly and tips.

Here is a screenshot of an interesting segment of the log.

When full throttle is requested the copter descends… I have already redone the ESC calibrations and the problem persists.

If anyone has any ideas, please help.

Thanks,
~Travis

It seems some motors are tilted. Motor3 and Motor4 working hard to maintain yaw stability, and when yawing is commanded motor4 saturates, other motors power down to compensate and lift is lost.