Canon 6D: battery blinks and camera’s off only with ML sd

[Opoloko]

Hi

I use ML regularly on my Canon 6D for astrophotography. I have latest ML for 6D and camera is powered by a battery adapter cable that powers the camera at correct parameters converting power from the mains like the rest of my equipment.

It all works good usually, but sometimes it happens the camera switches off showing battery symbol blinking.

As soon as I take off the ML card, or I reboot without ML, it works perfectly. Also without any SD card inserted. Then as soon as I insert the ML sdcard it switches off afgain with usual battery symbol flashing.

As this is completely random and sometimes doesn't happen for weeks, do you have any idea what that could be and what else I could test/debug to understand the problem?