You might want to turn up your speakers a little bit and listen closely. You can really hear the noise towards the end. In this video, I'll accelerate in the first part of the video, and brake with regular force. When I'm braking, you can hear the rumble rumble rumble sound, as if I'm going over constant bumps on the road. I don't think I physically feel the rumbling though. If I'm not braking, you can still hear it really faintly. I noticed that the noise became louder when I had my wheel all the way to one side, making a U-turn at the end of a small street.
Any ideas on what this is? I changed the brake pads, and then not too long after, I left my car in my backyard for about 3 months without touching it. Also had a check engine light on for a while now, but I decided to pump up the tires since they were getting a bit flat, and the check engine light disappeared. Hopefully the tires were triggering the light and it doesn't come back.