I will check one and see if I can duplicate. I'm guessing that there's something wrong with yours. I've seen the errors many times on AC power supply. Some times using on a DC power supply will work fine without error.

The problem of tricking at 10X the rate happens with what battery? and can it be the only battery being charged? I've not seen that error before , but will try it out. I'm afraid it sounds like a bad one too.