My E500 (2004) center dash speaker makes a rattle/buzz sound with midrange audio. How do I fix this? Can I replace the speaker? Can I remove the cover to inspect it?

it sounds like a loose connection to this center speaker, in some models you can remove the speaker cover to get access, if not removal of the dash is fairly easy if you know what you are doing take it to a car radio shop and ask if your speaker needs replacing which may turn out your best route