I had a stop on the NQ futures and it was not activated, even though the contract traded many times at the appropriate levels. After I noticed this and manually sold out many points lower, I called IB and after some investigation they said that the stop was in their system but not receiving any quote data. They said that this will occasionally happen. Besides the fact that it cost me extra money, this scares the shit out of me. I know IB has had problems with Naz stops, but not with Globex stops. Now I am scared to set a stop and walk away. Has anyone else had this problem?