Comment 1 for bug 725316

Hint: I found a work around. Though I have only installed the banshee package, it comes with some default extensions.

I went in the Menu to > Edit > Preferences > Extensions and un-checked ALL of them. Quit the program. Restart.

Not it works perfectly. Changing to Now Playing. Even changing to complete fullscreen.

Console output from this successful run/workaround:
(At the end it says something about "NowPlaying." however it works with all extensions disabled..., but this maybe a good hint)

$ banshee
[Info 23:45:41.543] Running Banshee 1.9.3: [Ubuntu natty (development branch) (linux-gnu, x86_64) @ 2011-02-20 07:36:24 UTC]
[Warn 23:45:41.955] DBus support could not be started. Disabling for this session.
[Warn 23:45:42.127] Cannot connect to NetworkManager or Wicd - An available, working network connection will be assumed

(Banshee:17261): GVFS-RemoteVolumeMonitor-WARNING **: invoking IsSupported() failed for remote volume monitor with dbus name org.gtk.Private.GduVolumeMonitor: org.freedesktop.DBus.Error.Spawn.ChildSignaled: Process /usr/lib/gvfs/gvfs-gdu-volume-monitor received signal 6

(Banshee:17261): Gtk-WARNING **: Could not find the icon 'context-pane-maximize'. The 'hicolor' theme
was not found either, perhaps you need to install it.
You can get a copy from:
        http://icon-theme.freedesktop.org/releases
[Warn 23:45:42.972] Caught an exception - GLib.GException: Icon 'process-working' not present in theme (in `gtk-sharp')
  at Gtk.IconTheme.LoadIcon (System.String icon_name, Int32 size, IconLookupFlags flags) [0x00000] in <filename unknown>:0
  at Banshee.Gui.Widgets.TaskStatusIcon..ctor () [0x00000] in <filename unknown>:0
[Info 23:45:43.163] Updating web proxy from GConf
[Info 23:45:43.205] All services are started 1.247349
[Info 23:45:44.097] nereid Client Started
Cannot connect to server socket err = No such file or directory
Cannot connect to server socket
jack server is not running or cannot be started
[Info 23:45:45.846] Uncached artwork size 34 requested
Cannot connect to server socket err = No such file or directory
Cannot connect to server socket
jack server is not running or cannot be started
[Info 23:45:48.634] GNOME screensaver service not found
[Warn 23:45:49.849] Could not configure libwnck support -

System.DllNotFoundException: libgobject-2.0.so (in `Banshee.NowPlaying.X11')
  at (wrapper managed-to-native) Banshee.NowPlaying.X11.FullscreenAdapter/WnckActiveWorkspaceMonitor:g_signal_connect_data (intptr,string,Banshee.NowPlaying.X11.FullscreenAdapter/WnckActiveWorkspaceMonitor/WnckActiveWorkspaceChangedHandler,intptr,intptr,uint)
  at Banshee.NowPlaying.X11.FullscreenAdapter+WnckActiveWorkspaceMonitor..cctor () [0x00000] in <filename unknown>:0
System.TypeInitializationException: An exception was thrown by the type initializer for WnckActiveWorkspaceMonitor (in `Banshee.NowPlaying.X11')
  at Banshee.NowPlaying.X11.FullscreenAdapter..ctor () [0x00000] in <filename unknown>:0
[Info 23:45:50.220] Inhibiting screensaver during fullscreen playback
[Info 23:45:51.248] Uninhibiting screensaver

$