I have a 2004 H466 with a galvonic isolator alert gizmo at my nav desk. I have my zincs and bottom serviced monthly so i am pretty confident that the zincs are all good Every now and then the alert starts buzzing and buzzing and buzzing. i disconnect from shore power and it stops. when i reconnect it may or may not start buzzing again. I am ready to simply cut the wires on it... thoughts?