MacBook keeps logging out of iCloud
I have a 2014 MacBook Air 13" that has been exhibiting some weird iCloud behavior I hope you can help me with. Between my phone and my iPad the computer is only used a handful of times a week, lately more often than not when I boot it up I find I have been logged out of iCloud services. iMessage, photos, iBooks, FaceTime, mail, etc etc. it's a little bit annoying because every time I have to set everything up from scratch, keychain, etc.
My phone and iPad inform me that iCloud has been set up on a new device. This is far from a new device yet it insists that it is. Is there a setting somewhere that I am missing? Or is it possibly a bug? Does anyone have a workaround or a solution, or maybe even a place to start troubleshooting.
I am on the latest Yosemite and have power nap enabled if that makes any difference.