Had the same problem on the start at first race with the Corvette on the bridge (chase cam). At the end of the race with the "podium scene", all the windows of the cars had white squares all over them. Some races later i had the same bug again on a different track with a different car. Its a only second or 2 that it appears, but its annoying. At the first pic you can see the grill is bugged with small white squares and the second pic is not mine. But it shows the problem more clear.