Clear-coat bump making white dots?

[zooropa]

Hi. I am working for a client at this moment. I was trying to give a bump to the coat of the metal.
So far I solver by applying it into the bump channel...

My initial idea was that the bump needed to be loaded in the clear-coat bump node.

Unfortunately this burns the scene. I tried with several materials in the same scene...and applying it to the bump of my metallic paint..all of those options work...

Do anyone of you experienced this ?

Thanks