We have replaced about all the parts you can replace on an Option 11 Meridian Mail Rel. 12 system. The AML link will drop out and it cannot be re-established until the MM is powered off and back on. When found down the MM green light will be flashing off and on. Once the MM is power cycled the Mail will come up and work for a couple of hours and then the AML link will go down for no apparent reason. Does anyone have any suggestions?