I have also experienced this issue twice with my EM5 nauticam housing. The first time was during a fresh water rinse at home and the second was during a dive. I have a leak sentinal and it did not change colour with the salt water leak, although the nauticam water detection alarm did trigger. I think the problem was related to operating buttons on the housing. It is with the dealer at present but so far they have been unable to reproduce the problem. I would be interested to hear if anyone else has had this issue and how they dealt with it (cause and solution).