My Firefox is taking between 150,000k-290,000K for two open tabs even though I'm running updated versions of all plugins/addons, what info do you need to help?

I'm running AVG free and have the most updated versions of all plugins/extensions. Memory consumption goes as high as 160,000k resting, no video streaming, and as high as 300,000k+ when streaming. Video will interrupt and stop loading arbitrarily, also will force dropped connection. Only use multiple tabs rarely multiple windows.