It looks like the message in your screenshot is not coming from Rhythmbox itself, but from the "Ubuntu One Music Store Rhythmbox Plugin" (see https://launchpad.net/rhythmbox-ubuntuone-music-store ). The text in question comes from ./umusicstore/MusicStoreWidget.py if you download rhythmbox-ubuntuone-music-store-0.1.10.tar.gz.
I'll attach a patch attempting to clean the message a bit, including fixing the OP's complaint. -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/702739 Title: typo in MP3 plugins are not installed section -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs