Very long post, I apologize in advance. So, after my son saw how well my Typhoon G flew, and after he flew it around a bit, he decided to pick up one for himself. After he received it, we met at my dad's place to do a very thorough pre-flight, and maiden her. After charging, hooking her up to the PC to check rotation, esc's and performing an accelerometer calibration, and going through it with a fine tooth comb, we took her outside to perform a compass calibration. All went well. I had used the same spot to calibrate mine several times, and my dad uses the area to calibrate his DJI P3S. Anyway, we lifted her up into a hover, and she was doing great. Until he flew it forward a bit. Then she went into a bit of a toilet bowl. Real quick, furtive movements. He let her stabilize in a hover. And she was hovering just a pretty as you please. I thought it was him just getting used to the sticks, but it wasn't. She was definitely acting goofy when we tried to get her to move in any direction. I figured that the compass calibration didn't take, so we did another. Same results. And another, in a different spot. Same results. I checked the telemetry, and it showed no compass errors. Defeated, we figured we would call Yuneec in the morning, and see what they said. Later, my dad went to calibrate his Phantom, and his software said that he was getting some magnetic interference, and it wouldn't calibrate. Bear in mind that he's used this spot COUNTLESS times, without a hitch. We had to move it over 50 feet from his normal calibration spot to get a good calibration, and BOOM his Phantom lived. I called my boy and told him to perform another compass calibration at his place, and give it another go. Sure enough, she flew perfect, in all modes. I should also note, that the Kp index was good, and I was using the teslameter app, and it didn't show any weird abnormalities either. The point of this freaking long post is, if you're getting some fish bowl, try calibrating somewhere else. FAR away from the initial site of the compass calibration, and give it another go. It worked for me.