I recommend http://www.anrman.co.uk
Maybe he can help!
My Bose X headsets probably have a problem with the Ear Speakers. I can transmit but I can’t ear nothing… I already tried to change the controller module with another BoseX headsets that are working fine, but I still can’t ear nothing.
So, I think that I need a shop that have the knowledge and spare parts to repair the speakers.