One embodiment of the present disclosure may take the form of an electronic device. The electronic device includes a housing defining a port and a cavity, a processing element contained within the cavity of the housing, an input/output device (such as, but not limited to, a sound wave transducer) in selective communication with the port, and a flow-blocking member movably connected to the housing. The flow-blocking member selectively prevents fluid-flow, such as the flow of air, through the port. The electronic device also includes a fluid repelling member connected to the housing and positioned in a flow path between the port and the input/output device.