I am running an ab dick with the aquamatic system (copper water roller). Recently have been getting about a 2" wide area near the middle, usually in non-image situations, where scumming is occurring. The water ductor roller looks very slick in that area (I assume emulsification) and the copper water roller builds up ink in that area as well. My question is: could the copper water roller become sensitized in that area, and if so, does it need to be conditioned from time to time such as periodically desensitized. Thanks for any help.