Search:

Waewell - if the color is in the plastic, then a plastic polish might work (Meguiar's PlastX idea).

Try a small test spot by hand and see how it goes.

If doing by machine, beware of high heat...

Waelwell-By chance do they seem to come and go.

Had clearcoat failure that would mimic water spots after it rained or heavy dew.

Looked like crap, but after a day in the sun, 9not so bad.
...

Have you tried claying too remove above surface contaminates? I would start there and proceed with caution on plastic. It heats up fast (rub a section with a compound oon a micro fiber towel !!).