I have a 2014 C7 and recently started having a problem with the passenger window. When we open the door the window goes down and inch or so to allow clearance of frame. Sometimes once it is opened, the window returns to the top position and hits the frame when closed. I have tried indexing the windows and this has not helped. One other thing to note is that when the door is open and I press the door open button (the one accessed from the outside) the window goes up and down a few times and then stops. This does not always happen, but on occasion. I am looking for others who have had and solved this problem.