I have an 05 420DA with original Raymarine electronics. I have played with various display settings, course up, heading up, etc, but can't seem to get my heading to consistently display straight up on the MFD. I have noticed that my MFD and my compass show the same number, but my autopilot is often off by 30 degrees or more, so I suspect the problem might be there. Perhaps the autopilot is providing incorrect heading info to the MFD? I don't have a manual so am not sure how to calibrate it, but I imagine that it can't be hard. Am I on the right track or should I be looking somewhere else? Thanks, all!