Initially, I connected GPS to the GPS port and i2c port on the APM 2.8. Then, it shows “bad compass health” and then some of the sources that I’ve looked they connected both of the GPS cables to the GPS upper and side port. Then I tried to connect like that and I can calibrate the compass normally and no “bad compass health” showed. Some people said I connected to the wrong port but it works fine for me. Finally, I’ve changed the cable back to the GPS port and i2c port, and then the “bad compass health” appears again. Any thoughts?