Headphones (Sony WH-1000XM4) are either "fully charged" or below 30% Work #Windows laptop claims my headphones battery is at 40%, always Personal #Linux laptop usually differs from what the headphones claim, when headphones say full, laptop says something between 50-100%, when headphones are below 30%, it usually says 10% higher. None of the numbers, not from the headphones themselves either, make much sense compared to actual time of use.