Critical sound block

I'd like to request a Sound block called "Speaker". Where the "Speaker" block is used to get the current volume of the default speaker device plugged in (this could be used for audio visualizers).

Scratch has a block that gets the current sound level from the Microphone, however for music playing on the device this doesn't work, so a block that gets the sound level from whatever speaker device is default (e.g a headphone, etc) would be god amazing.