2011 forest river wildcat 5th wheel.
Use a flashlight to look up at the fan when it’s off, also take the hood off and look from the top of the unit.
It sounds like something is up there hitting the fan. I have had mud daubers (wasps) build nests before and it sounds similar.
Mud dauber nest on one of the blades.
Sounds like an automatic card shuffler… Or something touching the fan blades or belt.
It actually sounds like the foam insulation around the unit is coming in to contact with the fan.
You’ll have to climb up top, pull the cover off the unit and you’ll be bale to see if it’s misaligned insulation, mud daubers, or something else.
I don’t think it’s an issue with the unit, but rather just an obstruction or impediment to smooth function.
I believe your plastic fan has broken. New fan cage needed
Source: Rooftop unit started making this concerning sound. What could it be?