I've only noticed it in the past few weeks, it smells musty and always smells of old cooked food and sweaty bodies.
Wtf can I do? I always open all the windows when I'm at home but as soon as I shut them and go out, when I come back I can smell it as I walk through the door.
I vacuum regularly so I wouldn't think it's that dirty and we have no pets, but we do have DC.