Comment 6 for bug 1398560

Additional discussion from the mailing list in late Nov:

Bogdan:
So, everything was fine today, until I noticed that the sound doesn't work. Alarms and ringtones work fine, but media sounds don't (such as Music). Moreover, there's no popup showing the volume change, although the icon in the notification panel gets updated. I am on the latest image (rtm, 10).

Sergio:
Yeah, I'm seeing the same

This is in the music log:
virtual QMediaService* AalServicePlugin::create(const QString&) "org.qt-project.
qt.mediaplayer"
Creating a new static Service instance
Failed to start a new media-hub player session: org.freedesktop.DBus.Error.NoRe
ply: Did not receive a reply. Possible causes include: the remote application di
d not send a reply, the message bus security policy blocked the reply, the reply
 timeout expired, or the network connection was broken.
Failed to create a new media player backend. Video playback will not function.
 (new media-hub landed on 11.27 http://people.canonical.com/~ogra/touch-image-stats/34.changes)

Yeah, I see it on every other boot, I'm also seeing this in media-hub logs:

client pkgname: com.ubuntu.music
uri: file:///home/phablet/Music/A/B.mp3
Client can access content in ~/Music or ~/Videos
void gstreamer::Playbin::reset_pipeline()

but when it works I see this added to that above:
Found audio content
void core::ubuntu::media::ServiceSkeleton::Private::handle_pause_other_sessions(const Ptr&)
video_height: 0, video_width: 0
Requested new system wakelock
play