I dont want to hear the background-game sounds while i wait for a game. Also it takes a lot of power so i cant play other games at same time while i wait for openRA. (well, i can, but it starts to lag a lot).
I noticed some maps actually changed this background-game, but im not sure if its possible to simply disable it, and i forgot how they changed it.
What is a background-game? That game which is playing under the menus, non-stop war against two AI's.
It's a scripted shellmap, game itself includes several of them and runs a random one when you start game client.
To disable it, go to Settings menu, find "Show Shellmap" and tick it off.