I had this problem on my windows PC, too. It started about two weeks ago. It happend at home and it happend at work on both PCs.
The funny thing was, it also started playing by itself, when I went away. And really strange was, that sometimes I had a song playing, I would never choose to hear. I am not sharing my spotify accoutn with anyone else.
I was connected to spotify via facebook. So I checked my facebook account and there it was. My account was used by devices in cities, I have never been. Of course I have disconneced those devices and changed my facebook password.
So if you might have this problem of suddly pausing music, go and check your facebook account. I don't have this problem anymore.
Im also having the same Problem, and I think its a Spotify-Software related problem, as this is happening to me on all my devices (ios, Win 10, Ubuntu 16.04, OSX Sierra). I already tried logging out all computers connected to the account. Not possible to play for longer than 20 seconds for me. Really annyoing 😞