I am experiencing this as well. Stuck at boot screen, no ssh access.
It was a sad moment. I had been working all week getting a board ready for a small set in a gig tonight - looper, new Overtone plugins, adding some sonic and arrangement spice to my songs. I had one last adjustment before heading out, just wanted to add a gain to my dry mic path to even it out and make sure all my gains were labeled and available on Knob 1. Then, as always, I reboot once or twice and verify that changes were saved and initial presets are as expected. We know what happens next 
I dug a Ditto Looper and TC Chorus out of a drawer and made the best of it; had a good time. 
Yes, I’m disappointed that I couldn’t use all the hard work I did from the last several days. These things happen and the best we can do is control what we can and move forward. A few things I know or believe:
- MOD is super committed to producing the best quality products they can with their team and process
- Moving hardware projects from prototype to production at any scale is incredibly challenging at legal, manufacturing, and technical levels
- Hardware fails, defects may not surface in small batches.
- For a team like MOD with vision and pride around their product, knowing users are experiencing failures is painful for them to learn about.
I had noticed some occasional odd behavior in the last couple weeks.
Symptoms:
- A week or two ago at a friend’s house after setting up the Duo kept being unresponsive when I would try to use the knobs or menus and it kept seeming like it locked up. They did have some old electric sockets and the extension cord seemed a little shabby. I fear some damage may have occurred here because the Duo operation seemed OK after I switched out to a heavy-duty extension cord I had brought.
- A few times recently after booting up, it looked like it was on the default pedalboard instead of the board I was just on. A reboot would fix it. Sometimes it seemed to take longer than normal to load the last board; several seconds after the boot finished, the screens would finally switch to show the mapped params.
- Several times recently I’ve had to reboot the Duo after connecting to USB to get the network to connect