Do an experiment. Hold a piece of paper by two adjacent corners up toward your mouth and blow across the top of the paper. The paper will rise up and maybe start flapping.
The principle at work here may or may not be part of what is causing the vibration. If it is, what is happening is that the static pressure on the side of the moving air becomes less than the static pressure on the calm side. This pressure differential causes a force to push the surface toward the lower-pressure side. If the surface is made of an elastic material like sheet metal, it will resist the bending force in an increasing amount the further it is flexed. At some point the resistance force will be greater than the force of the pressure differential and the surface will snap back toward its resting state. The cycle repeating over and over can cause the vibration.
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