I have noticed, in my months of running my nomad, if I have my tool out too far, it causes a vibration in the machine that causes a disconnection.
It seems like a safety feature to me. But as I read through the forums, many people are having disconnect issues, and I think "check the tool length" should be part of the troubleshooting process.
I find if I have my 1/8 endmill sticking out of the collet more then half an inch, it causes a disconnect.
Just a random thought. Who knows, it could help someone!