[startrek66]

I would ask if it is normal that I check on my quad. The operating condition is quadcopter  positioned on the ground on a flat surface. powered by battery and connected to gcs with usb cable. The system health reports all green lights. If I select in the settings Attitude complementary + Mag, I see the artificial horizon level. While if I select ins13 I see the artificial horizon tilted and unstable.

[DocHardinger]

usb connected could disturb mag orientation...better use oplink for telemetry and then check horizon again...could also be bad calibrated mag...

[TheOtherCliff]

INS13 adds mags to help leveling, so mags do this.  There are several reasons for this; global magnetic field map is not accurate, mounting the GPS/mag a little wrong, setting the mag rotation a few degrees incorrectly, stray magnetic fields...

It usually moves a little too.  Movement should be less than tilt.

Generally, what you see there is flyable, but will drift in Attitude mode.

You can make it perfect if you use this procedure.  Go to the section titled "Fine Tuning Your Hover To Stop Drift (Not Required)"
https://librepilot.atlassian.net/wiki/display/LPDOC/Aux+Mag+Setup+and+Calibration