Comment 7 for bug 1389761

I thought I was so clever in thinking of this idea, then I researched and discovered that it's what iOS already does. <https://developer.apple.com/library/ios/documentation/MediaPlayer/Reference/MPVolumeView_Class/index.html>

> The sound indicator does suppress the notification when it is shown

On the PC it does, but not on the phone. And if it's not obvious enough even for Canonical engineers to do it, that bodes ill for app developers. With this scheme, they get the notification-suppressing behavior for free whenever they choose the easy way of embedding a volume control.

> what if a notification goes off while the app is open ? you will suddenly adjust the notification volume.

Yes, that's a drawback. But then, a notification probably should temporarily quieten media playback, so changing the media volume wouldn't be that meaningful during those few seconds anyway.