Described is a solid wax mitigation barrier for a hearing aid that is cleanable via a simple wiping motion, is not a cause of irritation within the ear canal, and is acoustically transparent. In one embodiment, a wax barrier function is provided by a tube cap for fitting over the acoustic port tube of a hearing aid receiver. The tube cap may be constructed of an elastomeric high tear strength material so as create a small flexible acoustic tube cap that prevents direct ingress of wax into the hearing aid receiver. The design of the cap may also include a bridge that spans an acoustic port inlet so as to block direct material ingress.