I've had my 2014 MKZ for about 2 months now, and it has the THX audio system. My only complaint is that something in the front driver's side door rattles when I turn the volume up too high. And I'm not talking all THAT loud - I've never turned it up past halfway. But especially when the bass hits in a song that features a heavy bass, it honestly sounds like the speaker is blown. So I took it back to the dealer, and they replaced that speaker (under warranty). It still makes the noise. They told me this morning that it's something in the door panel that causes the noise, and there's nothing that can be done about it. Does anyone else have that problem, and have you found any solutions?
Thanks in advance for any help.