I bought my son a set of those cobra microtalk walkietalkies for Christmas and we put the batterries in them and on one of them you can talk and here yourself in the other walkie talkie, but when you talk in the other one, it's like talking to a wall. It kind of seems like the microphone that you're talking into is just dead. I've got them opened up and just "looking" to see if anythings loose and comparing the insides of the good and the bad. I've noticed on these 2 big cells or whatever they're called, that there are what looks like magic marker checkmarks like done by a quality check or something. on the one walkie, there's a green checkmark on both of the cells, on the other walkie, there's a green checkmark on the smaller cell, and on the cell that's right next to the button that you press to talk in to it, it has a red checkmark. Do you think that the one was checked and marked "BAD" by a red checkmark, and they put it in anyway? Any assistance in this matter would be greatly appreciated, Thank You.