Labview with Four Motors

Hello all,
A few days ago we tried to start programming our four motor robot using Labview so under the basicrobotmain vi we changed the default open2motor vi to the open4motor vi and then wired the additional two motors and set the inversion for those additional two motors. We used the default arcade drive. When we ran the program we could move forward, backward, and left. When we tried to move right we could move the joystick very slowly to the right and get it to work, but when we tried to make a hard right we lost all control to the system. Does anyone know what could be wrong? We don’t think its a wiring problem unfortunately. thanks.