Nearly each time I reboot my machine, the system panel and integrated app menus fail to load.

At a terminal, when issuing 'unity --reset', I get the following errors:

...
Initializing widget options...done
Initializing winrules options...done
Initializing wobbly options...done
ERROR 2012-11-05 04:36:48 unity.glib-gobject <unknown>:0 g_object_unref: assertion `G_IS_OBJECT (object)' failed
ERROR 2012-11-05 04:36:48 unity.gtk <unknown>:0 gtk_window_resize: assertion `width > 0' failed
WARN  2012-11-05 04:37:14 unity <unknown>:0 Unable to fetch children: No such interface `org.ayatana.bamf.view' on object at path /org/ayatana/bamf/application885622223

ERROR 2012-11-05 04:37:21 unity.glib-gobject <unknown>:0 g_object_set_qdata: assertion `G_IS_OBJECT (object)' failed
Setting Update "main_menu_key"
Setting Update "run_key"
WARN  2012-11-05 04:38:06 unity.iconloader IconLoader.cpp:438 Unable to load icon stock-person at size 24
WARN  2012-11-05 04:38:26 unity.glib.dbusproxy GLibDBusProxy.cpp:182 Unable to connect to proxy: Error calling StartServiceByName for com.canonical.Unity.Lens.Applications: Timeout was reached
WARN  2012-11-05 04:38:26 unity.glib.dbusproxy GLibDBusProxy.cpp:182 Unable to connect to proxy: Error calling StartServiceByName for com.canonical.Unity.Lens.Applications: Timeout was reached

The procedure hangs at this point.

Any ideas how to solve these problems ?

Thanks in advance.