Why does my volume go to zero randomly?

[Android Central Question]

My volume randomly goes to zero without me doing anything, I could be watching a video and suddenly with no warning, volume is now at zero. I have a second user on my device that I use for having a second account on some games, and whenever I would switch to that account I would set my volume to zero because I don't care about sounds in most noble games. I think that might have been the cause but I'm not sure.