Volara and Medicare

I have a friend who has been prescribed the Volara Airway Clearance device. She has been told by the company who manufacturers it that Medicare doesn't cover it, but she was under the assumption that they do based on her conversation with the prescribing doctor. Has anyone on this forum had experience with this Volara device and payment by Medicare? If so, I would appreciate so much any info you may have. Thank you in advance.