In Stock Android Oreo and below, by default, the volume rockers change the ring volume unless audio is playing. To adjust the media volume when the media is not playing, tap the down arrow next to the ringer volume control that appears at the top of the screen to see the option. Now Android 9.0 Pie has turned things around and brought media volume to the forefront.
If you press the volume control or the volume control on the side of your device on a Pixel smartphone with Android Pie, you will see the volume box appear on the right side of the screen, and "Media" will be the sound that matches the Press adjusts. You can tap the note icon to turn it on or off. You can also tap the arrow icon to change your Bluetooth output.
Like your ringtone, now the "Calls" switch is under the "Media" slider. Tapping taps the image between "Call," "Vibrate," and "Mute," similar to tapping the same icon in the ringtone slider that appeared in older versions of Android above. If you press the "Call" button for a long time, the "Sound" menu will open in the settings so that you can adjust both the volume of the ringtone and the volume.
Depending on how you use Android New feature may be a blessing or a nuisance. If you spend most of your time watching YouTube and listening to music, instant media volume access is highly appreciated. If you are the last and you get a crazy number of phone calls, you may prefer ringing volume as before, where media volume was only adjusted if you were actually playing media.