Why does my volume go up and down by itself?

[Android Central Question]

Doesn't matter if I'm streaming or listening to music saved on the phone. Doesn't matter if I use bluetooth or plug in headphones. Still does it

 

[anon(3641385)]

Doesn't matter if I'm streaming or listening to music saved on the phone. Doesn't matter if I use bluetooth or plug in headphones. Still does it

What phone brand have you got, and what version OS does it have?

Also, does your music app have a feature to play all music at the same volume? The Samsung music app does, for example.