Pixhawk 2.4.6 keeps losing compass calibration

For the second time this week, I went to arm my Pixhawk but it wouldn’t.

Hooked it up to Mission Planner, which informed me that the compass isn’t calibrated.

But it IS!

Last time I got this message, I recalibrated the compass and all was good.

Until now… and it’s telling me I need to calibrate.

Again!

Anybody have any idea why is it doing this? Is there an onboard battery I need to replace?

It’s a pain in the derrière to have to keep doing this as I have no option but to do it with USB cable connected.

You should use the wifi telemetryto connet flight controller