Strange audio playing when I shut down the phone (sometimes but not always)

Audio sometime plays when I shut down the phone. Not always but I always make sure all running apps are closed when I shutdown and have noticed no pattern as to when it will be triggered. It is annoying. I rooted the phone when it was new but decided to flash it back to stock with the original 6p image from google some time ago. I think this is being caused by an app I have installed but am not sure. The video below is not as clear as I would like, but there is no message being displayed, just the normal shutdown dialog and an icon in the status bar showing a media file is being played. Any help identifying what's going on is appreciated. It did this with Marshmallow and still does it with Nougat.

Here's a youtube link to a video of the issue.