I am amazed to find that this unit is still being shipped with this stand-out design weakness.
I bought my unit in Dec 2018. It's been stationary for most of the time, but I have taken it to different locations a few times. The USB jack always felt loose and it never seemed to properly go in the socket. I suspected it was a fragile connexion. I was right, as mine now intermittently cuts out.
I have been careful with the unit, but it seems that no amount of care can prevent these connexions from failing after being unplugging and plugging them in a few times.
I am really disappointed. Everything else about the device is fantastic, but if the thing won't charge, or unexpectedly cuts out, then it's not fit for purpose.