Abstract: Devices and methods for reducing undesirable noises relating to ostomy bag usage. One embodiment is a sleeve of foam or other sound absorbing material configured to surround substantially all or part of an ostomy bag. The sleeve can have a zippered bag opening to releasably receive the ostomy bag, and a stoma-coupling opening to enable a patient's stoma to be coupled to the ostomy bag. Another embodiment of the sleeve includes a pocket and an active noise cancellation device held in the pocket.