A respiratory pressure therapy device includes an enclosure including a first portion and a second portion, the second portion configured to engage the first portion in an assembled configuration, a blower to provide a supply of air for respiratory pressure therapy, the blower enclosed at least partially in the enclosure, and a blower inlet muffler comprising a noise attenuating material, the noise attenuating material configured and arranged to face a blower inlet of the blower such that an axis of the blower inlet passes through a thickness of the noise attenuating material, wherein each of the first portion and the second portion of the enclosure supports and retains at least a portion of the noise attenuating material facing the blower inlet in the enclosure.