I found it. Let me try and explain. The door panels bolt in with 4 screws, however, where the panel hooks over the door frame at the window, it doesn't secure to anything. It just sits there, ticking. My rear passenger door was doing this. I took the soft side of Velcro with adhesive backing, made a few strips and placed them up and over the door part nearest the window. I then took a longer strip of Velcro and lined the inner part of the panel that aligns with the door that I just lined out with smaller strips. Ticking gone. I hope this helps.