One of our big gripes with BlackBerry 10 was the fact that you weren't able to change the notification/ringer volume using the volume buttons. Surprisingly the buttons only allowed for media volume control, which just seemed kind of strange.
Thankfully in OS 10.1 you now have the option to choose what actions the volume buttons take - meaning you can set them to control either your notification volume or media volume by default.
To set this option, head to Settings > Main Volume
Under Volume Keys you can toggle the option on or off.
With the option off, the buttons will control your notification volume (when media isn't playing). With the option on, the buttons control the media volume full time.
Note here as well that you can toggle music shortcuts on or off so you can control your media using the volume keys.
Keep in mind this option is only available on OS 10.1 so if you're running OS 10 you won't see it available.
For more help and how-to be sure to check out all of our BlackBerry 10 Help Guides.