Yes, it can be reproduced.

[Steps]
- run rhythmbox in terminal
- add mms link in "Music -> New Internet Radio Station", in my case, input "mms://live.cri.cn/oldies/"
  The link will appear in the Radio window.
- double-click on the newly added mms link
  The error messages are displayed on the terminal. No sound.

The gstreamer libs installed in my Kubuntu:
wayne@Wayne-laptop:~$ dpkg-query -l gstreamer*
Desired=Unknown/Install/Remove/Purge/Hold
| Status=Not/Inst/Cfg-files/Unpacked/Failed-cfg/Half-inst/trig-aWait/Trig-pend
|/ Err?=(none)/Hold/Reinst-required/X=both-problems (Status,Err: uppercase=bad)
||/ Name                              Version                           Description
+++-=================================-=================================-==================================================================================
un  gstreamer-codec-install           <none>                            (no description available)
ii  gstreamer0.10-alsa                0.10.22-5                         GStreamer plugin for ALSA
un  gstreamer0.10-audiosink           <none>                            (no description available)
un  gstreamer0.10-audiosource         <none>                            (no description available)
ii  gstreamer0.10-ffmpeg              0.10.6.2-1ubuntu2                 FFmpeg plugin for GStreamer
un  gstreamer0.10-fluendo-mp3         <none>                            (no description available)
un  gstreamer0.10-fluendo-mpegdemux   <none>                            (no description available)
un  gstreamer0.10-fluendo-mpegmux     <none>                            (no description available)
ii  gstreamer0.10-gnomevfs            0.10.22-5                         GStreamer plugin for GnomeVFS
un  gstreamer0.10-pitfdll             <none>                            (no description available)
un  gstreamer0.10-plugins             <none>                            (no description available)
ii  gstreamer0.10-plugins-bad         0.10.11-2ubuntu1                  GStreamer plugins from the "bad" set
ii  gstreamer0.10-plugins-bad-multive 0.10.11-0ubuntu1                  GStreamer plugins from the "bad" set (Multiverse Variant)
ii  gstreamer0.10-plugins-base        0.10.22-5                         GStreamer plugins from the "base" set
ii  gstreamer0.10-plugins-base-apps   0.10.22-5                         GStreamer helper programs from the "base" set
un  gstreamer0.10-plugins-farsight    <none>                            (no description available)
ii  gstreamer0.10-plugins-good        0.10.14-1                         GStreamer plugins from the "good" set
un  gstreamer0.10-plugins-good-doc    <none>                            (no description available)
un  gstreamer0.10-plugins-really-bad  <none>                            (no description available)
ii  gstreamer0.10-plugins-ugly        0.10.10.2-1build1                 GStreamer plugins from the "ugly" set
ii  gstreamer0.10-pulseaudio          0.10.14-1                         GStreamer plugin for PulseAudio
ii  gstreamer0.10-schroedinger        1.0.5-1                           GStreamer plugin for encoding/decoding of Dirac video streams
ii  gstreamer0.10-tools               0.10.22-1                         Tools for use with GStreamer
un  gstreamer0.10-videosink           <none>                            (no description available)
un  gstreamer0.10-videosource         <none>                            (no description available)
un  gstreamer0.10-visualization       <none>                            (no description available)
ii  gstreamer0.10-x                   0.10.22-5                         GStreamer plugins for X11 and Pango

If any other info necessary for addressing this issue, don't hesitate to tell me.