The problem with Wi-Fi is that it can be brilliant at breakfast time and useless by lunchtime and you haven't changed anything, BUT, something, somewhere has changed, then you can spend hours and even days trying to find a fix for something that can be totally out of your control.
If you remove all the internal walls, water, electronic and electrical devices, metallic pipes and conduits and wrap the whole building in a thick lead shield you will have a good chance of getting decent Wi-Fi from an ISP Hub.
Many people have accepted that the VM Wi-Fi is poor and have purchased third party equipment that is much, much more powerful than the VM supplied kit and once set up have wondered why they waited for so long.
Just a few things that can affect Wi-Fi in the average home …
Mirrors, fish tanks, radiators, walls (some more than others), cordless phones, baby monitors, microwaves ovens, fridges & freezers, TVs, next doors Wi-Fi and Wi-Fi equipment, DAB transmitters, the list is endless.
***** If you think my answer has helped - please provide me with a Kudos rating and mark as Helpful Answer!! I do not work for Virgin Media - all opinions expressed are of my own and all answers are provided from my own and past experiences. Office 365, Dynamics CRM and Cloud Computing Jedi
Would be more helpful if you told us what Hub model you have, what devices is wifi dropping on, are they connecting to the 2.4 or 5 GHz bands, what other equipment you have connected, like do you have your own router? Also what are the Hub lights showing/doing when the "drops' occur?
Then, Mike is correct, but can you test whether its just a wifi issue or one that is affecting your physical network connection. The easiest way to do that is to connect a computer/laptop/etc to the Hub - directly with an ethernet cable and see if that loses/keeps a connection when the wifi drops.
Do that and report back
-------------------- John --------------------
My services: HD TV on VIP (+ Sky Sports & Movies & BT sport), x3 V6 boxes (1 wired 2 WiFi,) SH2 in modem mode with Airport Extreme Router. On VIVID200, Talk Anytime Phone, x2 Mobile SIM only iPhones.