Hello. I have two MT4BB units being used as low-current-draw digis on mountain tops. I am having an issue with them working for a few weeks/months/etc then falling off the the face of the earth. We know they have power as they're on the same power source as the VHF repeaters that are up there working fine. We have no reboot capability, at least not remotely, so I am wondering if anyone knows of an issue that would cause them to just lock up/halt without reason? It's infuriating as we picked them for their all-in-one design and simplicity. Now I am questioning if there is maybe something else we should be using. Anyone able to suggest why this might be happening or have any similar experiences?