Compass Calibration Errors

I’ve been trying to calibrate the compass on the navio 2, however I have unusually high offsets. (x: -659 Y: -460 z: 26)
I’m using the raspberry pi 2b with the navio 2, and I have tried calibrating it with just the pi and the navio without any peripherals connected as well as doing the calibration outside in order to avoid any magnetic interference and still receive the same offsets. Any suggestion on how to fix this?

thanks in advance, Chris

Similar thread going on here: Compass problem

I’m thinking about getting an external compass to see if there is any change in the offsets, perhaps there is something wrong with the internal compass. Are there any specific models I should look at that are compatible, or will any external compass modules work?