Not the same camera, but I have NINA installed on my portable system. I use a Canon 450d and at least 3 or 4 times a night the download from the camera to laptop fails. Also during polar alignment I have to switch the camera on and off in NINA to make it work. I at first thought it was NINA but have now found out the issue is with the laptop I am using and its ability to power the communications to the camera. This could be a similar issue