One of my original batteries died about a month ago so i bought 2 new M18 batteries off of ebay (in damaged packaging but new otherwise) and when i was on the job i noticed this problem. It happens with both of the m18 batteries when used with the drill, but the drill works perfect with the original battery. The m18 batteries also work fine in my impact driver. Im not sure what the problem is, seems like the overload protection is going on when the trigger is quickly pressed? If anybody has an idea of what might be the problem please let me know. Thanks. http://www.youtube.com/watch?v=8mDDouxkfig&feature=youtu.be