Installed an MICS-XC Rls. 5.0 with an 8-channel NAM (think it's 4.0) 35 days ago. Three times now, the NAM has completely shut down for no apparent reason. All call attempts to the auto attendant were "ring no answer." My tech, inputting feature 981 or 985, got no response. To restore service, we simply had to power off/on, and everything came back fine. My distributor says he's never heard such a thing. Just trying to find out if others have experienced the same thing. We have a similar problem with another NAM, earlier version. Thanks.