My battery monitor has started reporting incorrect voltage and amp readings. For the first few weeks the readings for voltage and amps were correctly reported. Then the voltage started to drop and the amp usage was reporting incorrect figures. Currently the voltage display for both the main and aux batteries is between 0.02-0.06V and the amp is reporting a positive flow of between 60-400 amps. This is with all batteries shut off at the main switch. I checked voltage and parasitic draw at the batteries and they appear within normal levels. I have replaced the fuses at the batteries and the RJ12 connectors between the shunt and monitor. Has anyone else seen this happen? I have this installed on a boat with lead acid batteries. Thank you.