Problem exists between shoes and carpet.
Possible solutions include:
Add humidity to RV
Change shoes/go barefoot
Since you are INSIDE the RV. though I will not rule out completly the posibility of a wiring problem.. the odds are low.
I did have a trailer once where it WAS a wiring problem, but I see that has already been addressed in another post. This trailer however was mostly plastic. To get a shock I had to touch two pieces of metal one of which was INSULATED from teh frame and one of which waS not. Turns out the orignal owner could not tell the difference between black aND white wires.