sanyo eneloop charger problem?

Why my sanyo charger turn off after 2 hours of charging, although the eneloop was fully discharge?
I switch off the charger and turn it back on, and i wonder the charger keep on charging the eneloop for approx. 7 hours. In another situation, my sanyo charger blue led(right side) turn off after 2-3 charging process, while the other side(left side) keep on charging for about 7 hours. Can anyone help me to solve this problem......please help me....
I afraid my sanyo charger was a "fake" charger.
(the manual said that the charger take about 7 hour to charge 4 eneloop batteries)