The two small dedicated UP & DOWN buttons on the right side of the phone to control the phone's volume.
Ringer Volume Levels
From any screen, you can use the UP & DOWN buttons to control the phone's volume for incoming notifications.
1-5: This controls the volume of the ringer for incoming calls or alerts like a message. If your *notification settings* are set to "Vibrate Only" or "Off", there will not be any alert sounds regardless of the manual volume level.
Vibrate Only: Vibrate only prevents the phone from making any sound for an incoming notification. This overrides your sound settings (If you have calls set to the sound "cosmos", but you use the volume buttons to put the phone in "Vibrate Only" mode, the phone will not ring, but vibrate only. You must press the volume UP button to raise the volume of the sound for those calls)
Nothing: This is essentially our "Do Not Disturb" feature. It overrides all of your notification settings and ensures that the phone will not vibrate or ring when you receive a phone call, message or alert.
Call / Speaker / Headset Volume Levels
The same dedicated volume buttons automatically control the volume of the speaker/headset while you are on a call.