I've got a bit of a strange one.
I use Linux 99% of the time however in the rare time I use Windows to game I often stay booted into it (as it overwrites my bootloader - thanks Windows). My computer wakes from Hibernate (and also Sleep) and I can't for the life of me figure out why it is doing so. It doesn't wake under Linux at all (from Sleep). I do use WOL however magic packets are not being sent to the computer and Windows is instructed to only wake with a magic packet is sent. I've also confirmed it isn't network activity as I've tried unplugging the computer from Ethernet.
powercfg -lastwake shows this:
PS C:\Users\micha> powercfg -lastwake
Wake History Count - 1
Wake History 
Wake Source Count - 0
Nothing in the event viewer either. I've tried following anything I can think of. Anyone else got any tips?