Comment 21 for bug 463102

I confirmed that the issue is in gstreamer as outlined above (actually in Karmic one has to use the command $ gst-launch-0.10 ).

I then changed Firefox's Preferences > Applications Action for the "MIDI audio" Content Type to "Use VLC Multimedia Plugin (compatible Totem 2.28.2) (in Firefox)" to restore the regression behaviour. I then updated the package from Karmic-proposed and tested.

Result: Firefox downloads the file, then opens a new Totem window and the file begins to play. Firefox's Preferences > Applications now shows the Action for the "MIDI audio" Content Type as "Use Movie Player (default)".

Thanks for fixing this so quickly.

Perhaps now we can look at getting gstreamer bad plug-ins 0.10.16 into Karmic-proposed? The release notes for are at http://gstreamer.freedesktop.org/releases/gst-plugins-bad/0.10.16.html
If this was to find it's way into Karmic-updates then we could add a new totem 2.28.2 package (with the MIDI support in the web browser plugin re-enabled) to Karmic-proposed.

@Id2ndR - I noticed that you seem to have also updated gstreamer0.10-plugins-base to the one in Karmic-proposed. I noticed that this was available but deselected it. I'm not sure if this is causing the issue you are experiencing, but if reverting to totem (2.28.2-0ubuntu2) (which had previously fixed the issue for you) does not fix the issue now then I think it is unrelated to totem (2.28.2-0ubuntu3). The gstreamer0.10-plugins-base currently in Karmic-proposed contains only one fix for bug #460535 if you want more info.