I would like to know how to mute a txt message notifications sound, call notification sound, or email notification sound while the screen is locked by just hitting the volume down button like every "dumb" phone on the face of the planet. I do not want to have to flip the screen or anything like that. I keep the phone in my pocket and would like to be able to just mute the sound by hitting the volume down button on the side of the phone in my pocket instead of having to take it out and unlock the screen and do it that way. Any help would be greatly appreciated.