When I wake up my phone started to decrease volume. If I do something about notification(like taking sms, phone calling) it decrease ringer+notifications and I can't change by the way there is no problem media+apps volume. But like notification if I do something about media this time there is no problem with ringer+notification but media+apps decreasing, it's unstoppable. Volume bar always top of my screen and cuz of that I can't use my return button I should close window with holding. What should I do?