Windows 8.1, Firefox v40.8.2 As of the last Firefox update, when my browser in on a page that contains video content, the program is somehow lowering the volume of any other application—such as an audio player. While this happens, the slider in Window's volume mixer for the app that's been stifled displays both the current, lowered setting, and a "ghost", semi-transparent setting (which represents where the volume was set before the video content appeared). After video playback, the other program's volume returns to the previously set level; in some cases, as in on some Facebook pages, just scrolling past embedded playable video or audio content on a page will cause the volume of any background apps to be lowered. Obviously, this is intentionally implemented behavior of the browser, or perhaps of some extension used by it. I don't want the browser to behave this way, so I'd like to know how to deactivate it.