Power supply from Adafruit (very reliable as most of us know). I can communicate with the unit for hours while working on scripts with no problems. I leave it unattended for a while, it locks up. I can substitute in my second board to see if the problem remains. I can do the same with the SD card as...

I don't have any other info to provide on this towards a solution but I have the exact same issue with mine. I have been using SSH and have also used the FTDI cable and terminal access. If it sits (seemingly) without access/interaction it always seems to lock up. This is an unmoded, out of the box m...