There was a thread recently where someone noticed that their Talon speed controllers (which are made in a similar fashion to the Victors) had been made with the input power wires reversed (red wire came out of the ground side, black wire came out of the + side). Check to make sure this is not an issue with your controllers as it's an easy thing to overlook, and very well might cause issues similar to what you described.
Edit: Sniped by Vex.
