Volume randomly lowers and go back to normal

[Trizorg]

My Android device (Galaxy Tab A, old type) just started randomly changing my volume to a very small setting and back to my normal volume I was at. This occurred randomly and I haven't done anything. I did a malware run through all of my apps and nothing seems suspicious. This hasn't been happening ever since last night. It's doing it right now because I'm listening to music. I'm not sure what happened but I will like some suggestions.

 

[SpookDroid]

are you receiving any notifications? If you set your device to mute notifications, does the variation in media volume happen?