@David-TP I appreciate your suggestions, however, I don't have this device any more, as I've returned it to the retailer after about a week of trying all sorts of tips. It was originally purchased on...

My PC is a Lenovo ThinkStation P310 running Windows 10 Pro. This T9UH has intermittent download speeds (not even 10 megabits consistently), and the network speed is intermittent, too. When it works...