My stock stereo on my 03 wrx has a speaker that is making a buzzing noise during most songs with decent bass. Its the front passenger side speaker by the floor on the door. I don't ever play the stereo loud (I'm usually listening to the engine) but it still makes a noise that is clearly audible. Is it possible that the speaker is blown? Any ideas on what is causing the buzzing / rattling noise?

 

Welcome to stock low end Subaru sound.