I use Ubuntu 12.04 LTS 64bit. When trying to play midi (.mid) file, it asks for a gstreamer plugin, but the Install button itself is unclickable.
Actually, I have
gstreamer0.10-plugins-bad (GStreamer plugins for mms, wavpack, quicktime, musepack -- without the (i386) at the end) installed already.
How do we solve this? Thanks in advance.