I just replace my whole driver side mirror on my accord due to a accident. Now during driving, I find the image othe mirror is shakey. The mirror is not loose from the actuator and all the screw are secure. Anyone knows why

 

Exactly the same thing is happning to me. I am wondering if I need to replace the motor mechanism.

 

since you said all screws are tight either the mount to the car is or to the actuator is loose it could be a screw or a mount point or bracket is broken but unless you know exactly what your doing the only simple fix is to replace the whole mirror