Phoning VM's crap offshore support often results in disappointment, I'm afraid.
Any more detail about whether problems are wireless or ethernet cable connected devices, what speed your connection is, what speeds you see, whether any particular uses are more affected than others?
Also would you try the following: Connect to the hub by clicking on this link http://192.168.0.1/ That should pull up the log in page for the hub. But don't log in, just click on the link "Check router status" That'll bring up a window with five tabs. Open the Downstream tab. Select all the text (Ctrl-A if using a keyboard), copy it (Ctrl-C), then paste it (Ctrl-V) into a reply here as TEXT not screenshots. Post that, do the same for the Upstream and Network log. You'll get an error message when you post the Network log, just click on "post" a second time.
Then we can check for any obvious problems with power, noise or error counts. This may show nothing, in which case there's other things we can look at, but it's a start.
