If it's plant that was upgaded this past winter well...there is people these days out splicing in the rain that pretty white powder is growing like sea monkeys you may just be starting to see it now .look which nodes were spliced when and I believe you will see a patern according to weather . Were you upgraded by one of those big national high production outfits??If so you will be able to tell which nodes will give you problems & when just look at sweep books & match too weather good luck homre