When starting Eclipse from terminal, if it prompts the error "Failed to load canberra-gtk-module", then this means you didn't install the module or you have installed the wrong version.
If you did not install it before, install with
sudo apt-get install libcanberra-gtk-module
If you have already installed it, but you still get the error, then try installing 32-bit version with
sudo apt-get install libcanberra-gtk-module:i386
Then the error should be gone. If you still get the error after installing two above, a reinstall with
sudo aptitude reinstall libcanberra-gtk-module