Original Herman Miller hard casters
If there are squeaking sound on usage when you just receive them.
You can isolate if it’s compatibility issues with your floor or the caster itself by having a piece of rug under.
If it’s the floor issue then a rug will continue to work, there are too much friction with the floor.
If it’s the caster issue, the lubricant inside haven’t evenly distribute yet and will eventually go off, but may come back.