Yea, I bought the skimmer off someone else & at some point in the assembly one of the darn grommets fell off. I had no idea there was suppose to be one there, since the top is rounded & it seems that it was intentionally made this way. That grommet fit nicely in that rounded indentation & the skimming world fell into place.
The noise was 3x-4x as loud without that grommet. This is some very small piece of rubber, so if there were any minor imperfections in the pump, I would imagine they would manifest themselves in what Kimoyo & myself are observing.
Thanks for responding Kimoyo, otherwise people would think me nutz!
Herman, maybe it's deaf in one ear & drink in the other hand? Man your little animation there is making me thirsty!