The gyro bubble is not moving.Is it the firmware or the gyros? Even tried factory reset, but not working.I am using stock firmware. Please help.

My KK5.5 had same problem, When I tried it first, every thing except pitch angle movements where working flawless, so thought the pitch gyro, is not working, but when I again flashed with same firmware (xcopter 4.7 by kaptain kuk), the pitch problem solved but then came the Lazy motor, problem .

Infact, I have two of these KK5.5 , which I couldn't make to work