Having the board with only the usb connected to the PC I can see on Baseflight how the 3d model spins around yaw axis and Heading value drifting so hard. Check the uploaded gif see what I am explaining. I need that heading value because I am developing a software for an autonomous drone. That is not a true representation of what your multirotor is actually doing, however it could be an indication that channels are not centered. For this, you would have to go into the receiver tab of the GUI and adjust the channels so that they centred at 1500 with endpoints at 1000-2000. However, in the configuration tab of the GUI and with the flight controller on a flat level surface, click on the "calibrate accelerometer button, this may smooth things out somewhat.
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