DC board is damaged again somehow and wonder why.

My Macbook a1342's battery did not charge and the magsafe light stayed green.

I replace the DC board and voila, the Macbook was back to live and magsafe light was orange. Charging went fast.

To see what would happen, I decided to unplug the magsafe from the machine while having the charger in the outlet. Than I plugged the magsafe back onto the machine and I heard and saw a sparkle. The charger has the correct value 60W a1344 for the Macbook a1342.

Now the light stay's green and charging is extremely slow. I am afraid the DC board is damaged again somehow and wonder why.