I think it would be better for you to stay with the firmware Version v6.6.1 stable (b1036).
The newest firmware is for developers to test. The main control features are for the most part the same in the newer firmware.
If your parameter file is good and the AQ board is level in your frame then there maybe a problem with your board.
A log should help to understand is it's a motor, ESC or other problem.
Have you flown the hexa with a different flight controller?
Larry