Problems with Xante Miryad 2 Plate, prints dots that are not imaged

Hi guys,
I hope somone can help me. I'm imaging Miriad 2 polyester plates with Xante 4 Platemaker. The are looking fine. Once I put it in the press, random dots appear all over the place. I have to clean them off but the are keep coming back eventhough there is not image. Did someone else experience this issue. I'm using rubber base van son inks and Varn universal pink fountain solution. I never used to have this issue, have it since a couple of months.