If you completely remove the compass and take it away from the boat and any magnetic interference, does it still behave this way?
I use the compass to help hold course at night and in the fog. It's a critical piece of navigation equipment for me. A few degrees is one thing, we're not making 1,000 NM passages trying to hit a small island. However, that is WAY out. I don't know if the calibration settings were designed for that much correction in mind.