I am running Banshee 2.6.2. Upon starting it up just now, I discovered I was unable to play any tracks. When I double-click a track or right-click and press "Play", nothing happens. Other functionality appears to be unaffected. Here is a log of the output when I run Banshee on the console, attempt to play a few tracks, and exit.
I can't think of what might have caused this, as it was working yesterday. I did just install one update (I am running Linux Mint 17), but it has nothing to do with music and the problem remains even if I removed the update.
I currently have the packages libdbus1.0-cil, libdbus2.0-cil, libdbus-glib1.0-cil, and libdbus-glib2.0-cil installed, all at their latest versions (0.7, 0.8, 0.5, and 0.6, respectively). Was there anything else to those instructions besides a series of diffs?