Dry run from terminal:
Thanks for taking a look.
(rhythmbox:4939): Gtk-CRITICAL **: gtk_css_provider_load_from_path: assertion 'path != NULL' failed
Traceback (most recent call last):
File "/usr/lib/rhythmbox/plugins/ubuntuone/ubuntuone.py", line 29, in <module>
'Purchased from Ubuntu One')
File "/usr/lib/python3.3/posixpath.py", line 92, in join
"components.") from None
TypeError: Can't mix strings and bytes in path components.
(rhythmbox:4939): libpeas-WARNING **: Error loading plugin 'ubuntuone'
Rhythmbox: could not connect to socket
Rhythmbox: No such file or directory
(rhythmbox:4939): GLib-GObject-CRITICAL **: Custom constructor for class SoupServer returned NULL (which is invalid). Unable to remove object from construction_objects list, so memory was probably just leaked. Please use GInitable instead.
[above on open and below on close]
(rhythmbox:4939): Gtk-WARNING **: mnemonic "s" wasn't removed for widget (0x1b16a50)
Unable to open ~/.mtpz-data for reading, MTPZ disabled.
I am more interested in helping Ubuntu/Rhythmbox than in solving this issue for myself. I am currently using Clementine on my hi-fi system (and my main machine is still running 10.04 which has no similar issues). But I advocate for Ubuntu and this is the default player, so it's an important issue.