Hi 1st off I'm new here so I might of posted this on the wrong place 😬
i drive a 2010 xB this morning as I was pulling out of my house I noticed when I hit the brakes or drive slow I hear a clunking noise in the back of my car any ideas where it's coming from also when I tap the brakes the noise is more noticeable inside my car also when I go over bumps in the rear of my car it's sounds like it hits metal to metal

 

Check you rear calipers to make sure everything is tight and that the slides are moving freely.

 

How many miles? If your rear brake calipers and slide pins look good, check the rear anti-sway bar bushings. The ID of these 2 rubber bushings should be round. If they're oval, they need to be replaced. The bushings are split so they're easy to remove and inspect. In my experience, they last 80k to100k miles.