You'd probably be ok installing gstreamer1.0-plugins-bad from Synaptic Package Manager (if it shows up in your Cinnamon 17 64-bit). The name is misleading a little, the description (in Synaptic or via a Google search) says...
"GStreamer Bad Plug-ins is a set of plug-ins that aren't up to par compared
to the rest. They might be close to being good quality, but they're missing
something - be it a good code review, some documentation, a set of tests, a
real live maintainer, or some actual wide use."
As it turns out I have it installed myself in LMDE so it's not going to break your system.
Just thought I'd suggest something else as this isn't the best plugin, but it's what Timidity uses. I forget why I needed to installed it myself (it wasn't for Timidity) but it's being used in one of my audio applications or other.