I'm under Xubuntu 13.04, with no additional repository or PPA.

I have a shortcut (<Super> + t) set to open the terminal with the drop down option. As I work along, this terminal can appear / disappear dozens of times an hour.

At some point, my shortcut doesn't trigger it anymore. But the space of the screen it used to occupy becomes unclickable.

Killing the terminal process is not enough : I have to restart.

If you need, I can send you more info, but I don't know how to proceed.