Hi MFCamisado, get out your contract and check the terms on "Minimum Guarunteed Speed", and refer to OfCom (See: https://www.ofcom.org.uk/phones-telecoms-and-internet/advice-for-consumers/advice/broadband-speeds-code-practice )
What you need to do right now is start taking speed tests using https://www.samknows.com/realspeed/ (Tests speed to router rather than just the PC so you can have stronger proof on it being Virgin's fault). Do this via ethernet as well as wifi because the Comms Ombudsman will accept lies by Virgin Media when they claim everything is a Wifi issue (even when the test clearly shows speed to the router).
Secondly, open an **official** complaint to Virgin using this webform: https://www.virginmedia.com/help/complaints
Be specific and factual that this is an issue with download speeds to the router regularly dropping below 1Mbps, and that you have tested this using SamKnows to confirm that this is the speed to the Hub, and not due to a local network fault.
You need to have several days of consecutive proof (3 days minimum) to prove that Virgin Media have broken your contract.
I will wager to you that after 2 months after your initial complaint, Virgin Media won't fix anything but will refer you to the Communications Ombudsman, which is where you will be able to submit your proof.
Now this is important, when you get to this stage you need to make the Comms Ombudsman's job as easy as possible, because they generally side with the ISPs. To make their job easy you should have all your evidence laid out nicely with times and dates marked beside every screenshot of the speed tests.
In your actual statement/complaint to the Ombudsman you need to cite the OfCom scheme https://www.ofcom.org.uk/phones-telecoms-and-internet/advice-for-consumers/advice/broadband-speeds-code-practice and specify that the speed has dropped below the minimum guarunteed speed for 3+ consecutive days.
If they do not uphold this complaint, you should escalate/challenge it for review by OfCom because this is quite a clear-cut violation.
Virgin **will** claim some bollox about "advertised speed is a maximum there is no speed guaruntee", but your contract does in fact specify a minimum guaranteed speed which Virgin have signed up to voluntarily. If the Ombudmsan doesn't uphold it and claims something about intermittant faults not being covered, you should escalate and complain to OfCom.
People are sometimes confused into thinking the Comms Ombudsman is a government body or a regulator, when it is in fact actually a private company that ISPs like Virgin Media pay to act as a sort of escalated complaint handling department. This exists to avoid real regulation by OfCom, so you may need to escalate to OfCom if they don't take your side on a clear breach of contract.