Abstract: Watertight enclosures for digital audio devices include one or more diaphragms for transmitting sound to and/or from the digital device's audio transducers, such as speakers and microphones. To mitigate standing waves and/or prominent natural frequencies, a central portion of the diaphragm is wavy with a relatively low Q (Young's modulus). The central portion is encircled by a peripheral web portion that is relatively thin to provide the central portion with spring support. In some examples, the diaphragm also includes a seal for sealing against the digital device's housing to create a generally closed air chamber between the diaphragm and the audio transducer. The closed air chamber promotes sound transfer between the diaphragm and the audio transducer. The closed air chamber can also reduce crosstalk between a microphone and a proximate speaker. In some examples, a relatively soft diaphragm and a harder enclosure are created using plastic injection overmolding.