Comment 87 for bug 486154

Thomas, Pete:

Problems with the system bell are subtle and strongly dependent on what exactly you are trying to do. One of these factors is the window manager. This bug is primarily focused on getting the system bell working under Metacity. gconf twiddling *may* be necessary in this case; Pulse Audio commands will do nothing. If you are trying to get the system bell working under Compiz or Unity, please see bug #769314.

I would have thought the simple fact that the system bell depends on window manager would be enough to convince people that the whole system needs a re-think, but apparently not.