that charger only puts out about 7 - 7.5 amps on wall power. Reduce your wall power settings to 7amp or below and it should be fine.

on DC power you can run a full 10amps

edit: on second thought, what batteries are you charging? the 7-7.5amp comment only applies to 7.4v lipos. If your charging 3S or bigger you will need to use an even lower amp setting.