Genesis 3-button controller, 2 models, 1 problem!

I have two three buttons controller (Model No. 1650), one Made in China and one Made in Japan. They have different PCBs, but they both have buttons A and B dead. Cleaned them, but doesn't change anything. I checked if contact was made while pressing the button and it does, so buttons work. I checked the pinout and A and B are on the same wire (#9). I re-soldered the connection, still nothing.

Could the chip on both controller have the same defect?

 

OK, I wrote too fast. Went nuts with the soldering iron and it fixed the "made in Japan" one. That's a relief because it's the one with the most complicated PCB.

I guess I'll just go over all the connection on the other one.

 

So, decided to order a new IC, since everything points to that. We'll see how it goes.

 

All right, so the IC was not the problem! Turns out it was +5v pin in the controller connector that was the culprit. Cleaned it, works perfect now. What's strange it's that even if it works perfect plugged in the console, it doesn't work when I use a extension but those work with my cheap chinese 6-button replicas!?