Does the photo below show the problem you have experienced with HP Professional Satin? The lines are imperceptible to me before the paper runs through the machine, but look like indentations with a slight sheen differential from the surrounding paper surface. Now that I've seen both, I now know that these are not starwheel marks.
I've run 600 square feet of the stuff through my 3100 and never once had a tech support person acknowledge that there were know manufacturing defects with this paper. Because of the intermittent nature of the problem, it has been really difficult to pinpoint the exact problem for me. I had HP replace my starwheels and the paper outfeed platen, to no avail. I thought that a tech support suggestion to pull additional media off of the roll in back to lessen the tension on the drive wheels was solving the problem, but now think that it was an unfortunate coincidence that my problem went away because of a good batch of paper, not a change in the printing process.
If this is indeed a known problem to HP, we can only surmise that they are continuing to sell the paper because not enough people are complaining to make it worth it to them to pull it off the shelf. I find it extremely disappointing that HP would stonewall me about this, but also take a little solace in the thought that it is fixable with better quality control over the paper manufacturing.
(The shot is taken with on camera flash pointing straight into the print to try to show the texture. This isn't an easy thing to photograph.)