I was 75% into a 4 hour print when my Maxx just stopped. I pulled up MC, no Issues. I loked at the LCD screen, Buffer is at ZERO. I have never sen the buffer below 9 during a print. I tried pausing the print in MC, Nothing happened. In Device Manager the RAMBo is said to be working properly. Then I notice that the Bed/Extruder temps are no longer updating.
I have had MC go brain dead a couple of times. but that was at the beginning of the print. Then I close/open MC, shut down/tirn on my Maxx, unplug/plug the USB.
considering I'm in the middle of a print, I'm kind of reluctant to do anything drastic. But I may have no choice.
UPDATE - I had to do the drastic thing.
I tried to unplug/plug in the USB - COM 3 Unavailable. Cycle the Maxx's power - COM 3 Unavailable. Close/Open MC - COM 3 Unavailable. Tried USB again - Now I'm able to connect. 
