Of course, the one time I go on there that I try to replicate the issue, it doesn't come up. From what I have experienced, it only happens at KDFW, not KLAS, with/without cloud shadows. I know I have issues when I start at DFW, but today I was doing BOS to DFW, and coming over the numbers on 35C is when it popped up. The whole flight I was at 30fps and then there I was at like 5.
I just tested it with default and non-default aircraft, with/without shadows and seemed to have no issue. I guess I will post again whenever I can grab a pic of it.