Brian H suggested "going through a hub and not directly to a USB computer port". I understand what he is suggesting but it used to work properly -- in fact I think the USB Interface has always been connected through a port here.
I would still try going directly to a computer USB port to rule it out. I have seen many devices, USB hubs included that flake out on some devices. The thing with electronics is that it can work one minute and fail the next.
Hi dbemowsk!
Appears you were correct! Finally dawned on me there are two USB ports on the front of the computer, under the cover. ...Now where did I put those spare USB extension cables?? <g> Tested; very surprised to see the USB Interface now stayed connected!
Did order a replacement hub the other day as was a good price; looks like I'll be using it sooner than expected! Will also look into putting additional USB ports in the computer (PCI to USB adapter) - currently all four ports in use (keyboard, mouse, UPS, USB Hub).