oceanic datamask -when sould it be serviced and what is done?

[guytt]

hi
i have an oceanic data mask which has been used for a few years and i was wondering when should it be sent to service to oceanic?
also what is the service procedure ans what is done to the mask?
at oceanic site there is info about service but it does not elaborate what is done and it specifies that the prices reflect service for the mask only (i.e. not the computer or hud display???) so when and how are they serviced?
hope to have your inputs in this issue