The OP’s situation definitely sounds like a trainer specific issue. The KICKR has a 10.5 lb. flywheel spinning at high speed. Some of these flywheels are better balanced than others. I’ve had several KICKR’s and some of them shook the entire house. Wahoo support is fantastic. They measure the vibration levels of their returned/refurbished units and sent me one with a lower level of vibration. But it’s not perfect.
The speed at which you get the resonance will depend on your set-up - mostly on what’s underneath your trainer. If your trainer is over a soft spot in the floor, the resonance will occur at a lower speed.
My trainer is set-up in the room next to a sleeping child, so I added an isolation platform made from 3/4" plywood and appliance isolation pads. That sits on top of a vibration absorbing mat, which is on carpet with thick carpet padding underneath. And that’s over a wooden floor.
Another thread on this topic → Am I going to get an angry knock my door