Robot dog -problems

i’m building a robo-dog and i’m using 13 servos. the servos are powered by 5v and 3A but when i connect them to controller (mini-maestro 18 chanels), some of them starting to jump and go crazy. i dissconnected all of them and connect them one by one and when i connected nine servos in a raw its going wild.
can anyone please direct me to the problem


Do you mean that if you have less than 9 servos they work fine? It’s probably a power issue. A low current estimate for 13 servos would be 9.75A. If using fewer servos works fine, then you probably just need a higher current power supply. I would suggest 12 or 15A.