First problem is your husband, if he can't trust the maid, then he need to help in taking care of the baby. You don't speak out don't mean you don't mind so you have to tell your husband how you feel.
And I think whether a maid is good or not we, wives ,can make a better judgemnet than men. So if you think you want to change go ahead and talk to your husband. Since some maids are good.