I recall there was an issue with white balance on the GX10 that was fixed with firmware update 1.0.2.0:
https://canoncanada.custhelp.com/app/answers/answer_view/a_id/1032128/~/canon-4k-camcorder-vixia-gx1...
"Changes in Firmware Version 1.0.2.0:
1. Fixes a white balance error that may occur when using Auto mode or a Special Scene mode* depending on usage conditions.
* Portrait/Sports/Night Scene/Snow/Low Light/Spotlight"
Could that be your issue ?
