Thank you, this took me four hours to resolve.
I tried this
Type below command in terminal for fix the issue
sudo apt-get install ubuntu-restricted-extras
the install additional codecs from edit>music>mp3
and uninstalling then reinstalling rhythmbox
and deleting my entire music folder and redownloading it from my external drive
and all the silly gstreamer posts
what finally did it >>
I clicked on "import errors" on the left side of the screen (near the playlists)
I needed a bunch of codecs
in the bottom right corner clicked the install plugins
and waited 10 minutes while it figured out what it was supposed to do...
then it was pretty much next next, yes yes
patience helped me resolve this issue... and you!!! thank you