Sounds more to me like the actual keyless entry module may be bad, it might not be a bad door lock actuator itself. I am no Honda expert but on my wife's 2003 Accord the keyless entry unit is an internal part of the driver's side door lock switch assembly. If yours is the same, maybe you could unplug it temporarily and see if the door lock still has a mind of its own, then go from there with how to fix it.