Hi guys, make sure you havnt just locked the app you are trying to change the volume on.
Press recents key
Look for little padlock on the app and make sure its unlocked.
see in the image youtube is locked so if i have it open i cant change the volume but if i unlocked it then i would.
i know this is simple but it fooled me at first to thinking my button wasnt working. i would imagine this is some peoples issue . accidently hitting the lock when using recents. so it would seem restarting would fix it as it would reset all the locked apps to default to unlocked.
I registered just to post this. so hope it helps someone. cheers guys and girls.
I've had my phone for about a week now (normal s7) and had this happen this morning. Power button wouldn't turn on screen/do anything and volume down wouldn't do anything. Had to use the home button to get the screen to respond. After holding down the power button and volume down I was able to reset the phone and the issue is no longer present. Should I just assume this was some kind of software hiccup or should I go the route of trying to get it replaced for being defective? I've seen a few posts on reddit and some other forums, seems like an issue that is starting to pop up for quite a few people. Any help would be awesome. Thanks guys.