Very High Compass Offsets

I recently upgraded to a Pixhawk and purchased the external GPS and stand for my quad. I wired everything up and calibrated everything the same way I have been for my previous controller and I am getting very high compass offsets for the external compass, but good offsets for the internal compass.

Internal
X: -94
Y: 8
Z: 108

External
X: 161
Y: -456
Z: -321

My yaw obviously was extremely unstable and would rotate and drift. When I was doing auto trim, it nearly spun out of control. For now, my fix is to use the internal compass and everything works great. Loiter works perfectly and my heading is rock solid so far.

It is mounted near the center of the aircraft on the 3DR post. No metal is near it, and the two wires wrap around the post once. It is pointed in the correct direction :smiley:

Any suggestion on how to fix this? It isn’t the biggest problem in the world because the internal works fine, but I paid for an external compass and it doesn’t really work!

Are you positive that’s not backwards?? It’s normally the internal is the problem with high offsets.