Motors spinning at different RPMs for a F450 Quadcopter Pixhawk 2.4.8


I am building a F450 quadcopter and the motors seem to spinning at different RPMs when I increase throttle (as seen in Actuator Outputs (Main) in the log while testing it without propeller on bench. Attached log file: Flight Review

And when i fly with propellers, the quadcopter is not stable and oscillates along roll and pitch axis.

Can someone please help me understand what am I doing wrong here?

Alvin Anthony