This is caused by vibration. (and I'm not that much of a "guru" on the 3GX lmao). I would suggest doubling up your tape under it, or getting some kind of gel tape. I can't remember what it's called, but it's a greenish color and very soft. YOu have to run a zip tie lightly over the gyro to keep it from moving too much. And you will put fuel line over the zip tie to again, stop vibrations. I'm sure if Gaba gets on here, he can post a picture of his helicopter where he has done this.
Ah, it's called "Zeal Tape".