Windows 7 has an option to independently set the volume of every application currently running in the volume mixer, along with a separate option for "System Sounds" which impacts the sound scheme the user has set up. So, for instance, if you have a certain sound set up for exiting windows and you set the "System Sounds" volume to 25%, it will play the exit Windows sound at 25% volume the next time you exit windows. Well, there are two windows sounds for menus - they're called "Menu Popup" and "Menu Command" for when you open a menu (such as the start menu) and when you execute a command from that menu, respectively. I have such sounds set up on my system, but mine are somewhat loud, so I have the "System Sounds" setting pretty low on my system. It used to be that Firefox didn't play menu popup and menu command sounds at all, but in a relatively recent version that was enabled. The problem is that when clicking through menus Firefox doesn't seem to respect the System Sounds volume setting in Windows 7, but instead uses the Firefox volume setting, which I have all the way up. That is not normal behavior for most Windows applications. For instance, if you open Winamp and right-click in the middle of the application, you'll get a menu popup sound at the System Sounds volume level, not the Winamp volume level. It's a minor annoyance, but it'd be really nice if Firefox either worked like most applications, or had an option to disable menu popup/command sounds completely just for Firefox. == This happened == Every time Firefox opened == Firefox started using menu popup/command sounds