@jan That's definitely not normal behaviour.
I updated mine to the current version via a hub, using Windows 7. It probably depends on the hub though. I think the problem with some of them is that there's a voltage drop, due to the cables, and the hub doesn't necessarily correct it. It would certainly be possible to design one that did, using a DC-DC converter, but I don't know how many do.
Using good quality cables helps with the voltage drop - the better the wires in the cable conduct, the lower the drop in voltage.
It may be better to try an adapter, rather than a hub, if you don't have USB A sockets - assuming you have some other sort of USB socket. On eBay, you can find simple adapters, which are two different connectors back to back, or short cables, to adapt just about any sort of USB connection. The ones to avoid are OTG cables and adapters. Other than that, they tend to work well.
Are you sure the update completed? The fact that it asks for it again suggests that it didn't.