JaidynM - thank you for your response.
Both hubs are connected to USB ports on the motherboard, by standard USB cables, and are powered. I do not have them 'daisy-chained'
I have downloaded Driver Manager, and it has identified 4 out of date drivers. When I go to update them using its interface, it prompts me to pay for the application. While I am, in general, happy to pay for software that is of benefit to me, it will only give me the option to buy a 10 PC Family Pack for nearly £50. I have tried to find a web site that may give me other options, but cannot. Have you got any suggestions as I only need a single PC license, or 2 at the most?