Found the auto on/off and adjusted it. Still shuts off though unexpectedly, have noticed sometimes it's because power cord is bumped. But not all times.
Safe to say the power cord is the culprit, as you say sometimes when it is bumped it happens, other times not. Loose connection possible where you cannot see. Try adjusting tension and slack in the line, different angles, etc, possibly change to different outlet, different USB power cord if you have one.
Does this problem occur when you are using straight battery power? I did not read anything about battery power vs. USB/power sources and if it occurs no matter what power source you are using. Process of elimination here, fiddle with this, change that, etc, and you'll figure it out. Seek and ye shall find.
I had the same problem out of the box and the auto on/off shutoff was my fix.
Good luck with that!
JD
kf4anc