Try rebooting your router. Unplug it from the mains, leave it for a few minutes, then plug it back in. It'll take a minute or two to reboot.
No, you have a basic issue - no software add-on is going to fix that. Internet "boosters" are rarely of much use on broadband anyway.
I may also be a router/cable modem fault, or a cable fault somewhere - so try calling Virgin and see what they have to say.