I like and use the Hobbico Elite a lot. However, the AC/DC power supply that comes with it is a bare minimum design, poor filtering primarily. After the power supplly for mine failed, I use a converted PC supply for the 12 volts as the charger itself works very well. The erratic operation with the original AC/DC supply is what led me to the discovery that it was not the charger acting up, just the prime power to the charger was causing the bad operation. To see if that is your problem, just run the charger off a 12 volt battery and see if all works as it should.