Stock stereo vibrating under bass

When listening to the stock radio and you turn the volume up a little bit, whenever there is bass in the music, there is something in the car vibrating making it sound like sh*t. It seems to be coming from the middle area somewhere around where the computer plug / handbrake area is. I tried to find exactly where it is coming from but couldn't.



Has anyone had this before or know where the vibrating sound is emitting from?