We are running NXT-G, version 1.1 with firmware 1.05. Someone in our workshop wrote a 1-block program to make motor b,c go forward for 5 rotations. When the program runs, one motor stops spinning immediately - while the other continues to the full 5 rotations. We've switched the motors, the wires, the ports (changing the program accordingly), and even the NXT Bricks. None of these changes have resulted in the brick running the program properly.

Any ideas?