Best polish for travel trailer

I have found that Turtle wax and Mcquires seem to work nicely but when the evening light shines one them just right, there are these odd area's that look like you just smeared oxidation around. Using more polish just smears is around differently.
At first I thought it was that my TT was 13 years old but it does the same thing on our new one. This is for a white finish. It doesn't seem to do it much on a dark finish.
I'm still looking for a wax that wont cause this.