When towing (single axle trailer/ Procraft boat) whenever I hit uneven road surfaces or dips the trailer flexes and the tires squish if that makes sense.
The trailer bounced a few times where the transom safer actually shifted on the rear roller.
I dont exceed the speed limit and try to slow down if I see uneven roads to try to prevent this.
Tires are at maximum pressure of 50psi.

Is this normal for a single axle trailer?

Do I need new springs?