Switch to Mono Sound Output with the Left Right Sound Select Plug-In
The Left Right Sound Select is a simple plug-in that lets you switch the sound output of web pages from stereo to mono left or right easily and quickly by clicking a button on the browser’s address bar. This functionality is useful for videos with dual-language tracks as many videos on the internet utilize the left and right audio tracks for dual-language channels. With this extension installed, you can switch between the two sound outputs conveniently.
It works for websites that support the Chrome extension. You can use it for any web page that contains left and right audio tracks and allows you to switch between the two audio tracks easily and quickly.