I have a rattle coming from the rear passenger side that kicks in on rough road

Thanx for the tip...i will try today I followed your suggestion and every-time I hit a rough spot when I gently applied the brakes the noise stopped only to return immediately when I took my foot off the brake./ I brought to shop where work was done and said I feel pretty certain that the brake hardware/calaphir should be checked. He said we did that already and that it could be a linkage rod etc but will give a thorough look if I can leave the car for a few hours. My question is can it be something different than the brake?