Don't know if it helps for your year, but I have a Vista that about six years older, that had the same issue. I bought it used and found some funny evidence that it was driving the previous owner about half crazy, as there was a massive amount of duct tape residue all over the upper screen door frame.
I went to the Winny section of IRV2 and did some research. I then went out to the rig, and wrapped two or three layers of electrical tape around the latch post on the door frame. This is the 1/2" smooth bolt that the latch catches. That totally eliminated the problem. Eventually, in use, the door latch "bites" through the tape and starts banging on the post again. So it takes another $.02 worth of cheap electrical tape, and two minutes to fix it again. I've done the same thing to a 2010 Vista a friend owned, and it worked. Hope it works for you.