Have your trailer tires balanced
Most RV tires are not balanced from the factory.
It might not seem like a big deal but............
Think of all the stuff you have in that trailer, and the walls and roof and the framing.... Reducing the vibration can only help. Ever ride in a car or truck with one or more wheels out of balance?? Balancing will also help improve the life of the tires. Only cost a few dollars per tire. It's worth it.
Remember, this isn't a flatbed farm trailer used for hauling hay.