I got one of the X-Force bars for my WW. It works great but first time I used it the whole thing vibrated pretty bad so I took all the nozzles off and cleaned them.
This helped but still has an ‘out of balance’ feel. Today I flipped it over and you can see it like a slightly warped car wheel. Am I looking at a new swivel or something else?
When cleaning it sounds like a really fast steam train.
I had some x force problems with the original design. The arms and arm ends would not stay in place, and caused great problems. I spoke with them and they honored the warranty. Check the arm and the arm ends, and see is there is any play. Swivel shouldn’t suddenly wobble unless you hit/ran over something. Sometimes a loose swivel mounting bolt can cause it, also.