Share your experience!
I've had the xz3 for 2 days and cannot get the volume rocker to adjust ringtone volume. Its only doing media but there are no apps open to cause this. Very frustrating as cant seem to find out cause.
The volume rocker adjusts the media volume. It adjusts ringtone volume only when the phone is ringing.
You can press on the gear wheel icon to change all the volumes available.
You cannot change this behaviour as it's coming by default with Google Android 9.
Hi @lloydy1, welcome to our forum and congratulations on your device.
As @skycamefalling mentioned, this is the default behaviour for when you change the volume in Android Pie and there is no setting that will change the media sound to ring and notification tone.
If you want to adjust the ring and notification tone, you will have to tap on the cogwheel/Settings at the bottom of the volume controller and it will open up the Sound settings, or you can go to Settings > Sound and the same menu will be shown.
Have a nice day! 
There's a workaround for the people who want to control ringer and notification volume when pressing the volume buttons. Simple install Button Mapper v0.73 APK, grant it accessibility permission, then map your volume up button to "Volume up" and volume down button to "Volume down". This will make the volume buttons control ringtone and notification volume by default and you'll see 2 sliders on-screen: one for ringtones and the other for media.
Note: DO NOT install later versions of this app, you'll find this feature requires a paid subscription (unless you want to support the developer, of course).