Anyone else having problems with volume sticking? I have a 6 Plus. I suspect it's a software bug because the buttons will not fix this. It has happened twice now. I listen to music over Bluetooth in my car with the screen on. When I shut the car off and open the door, I turn the screen off and slip the phone in my pocket. The first time I heard the volume falling before I opened the door. I looked at the phone and as soon as it was unlocked, the volume heads up display was on and stayed on. I hit the volume down and up buttons. No change with the down button, but the up button would take it up 1 notch, but it instandly went back down. It just did it now but the opposite direction; volume up. Both times rebooting the phone as fixed the issue. Has anyone else encountered this?