Odd Pictures Showing Up in my OneDrive

Hi all,

I've been seening some black pictures show up in my camera roll. The pictures are always labelled accordingly, so I know they come from my Surface and my 1520. I've also checked the time stamps on the pictues and found they're being taken late at night, times I wouldn't be up. Usually three or four picutres will show up every week, but on occasion about 20 will be taken. I assume my phone takes pictures unprovoked at night, because sometimes it will launch the camera app while I'm using the phone. Does anyone else have the mysterious black picture problem?