What kind of adjustments can you make?
For example, my skimmer I can adjust a few things -
I can adjust the level of the surrounding water in the sump where it sits (It's an in-sump skimmer) by adjusting my ATO float valve.. I can adjust the amount of air I let get into the venturi by using a screw... and I can adjust the outlet size to put back pressure on the cylinder. If any of those three things changes, the skimmer needs to be re-dialed in. And so that translates into if any of those three things changes, the effluent that collects will vary greatly from a pudding like gooey tar to murky or cloudy water. It depends on how wet you want to skim.
Skimmers also need time to break in as Marlene mentioned as well so you are probably just experiencing that, just keep the above in mind as well. They have a mind of their own.
Also, every couple of weeks I let my venturi slurp in a cup of RO/DI water to flush the tube otherwise it gets salt spray buildup and restricts the flow, and throws my dial off.