@rotahn You have what I refer to as a CBU fault. That's where something's evidently wrong, but VM go "errr....completely beyond us", and then there's stuff all progress, with the company completely unable to fix a problem, and the whole process becomes a Kafkaesque comedy of repeated contact with the company, multiple apologies, denial of fault, lots of "how's your connection working now" enquiries, all overlaid by the complete inability to find and fix what ought to be a bread and butter problem on VM's wholly owned, wholly managed network. A comedy other for the fact that it's not funny except for VM's competitors.
It would seem VM are not going to take ownership and sort this proactively; the company's systems are designed to make good customer service very difficult even when individually staff do want to help you. With that in mind I suggest you go back to the excellent advice given by @jem101 earlier in this thread. Formal complaint using the form in My Virgin Media, asking for them to (a) sort their technology and give you the speed you're paying for, (b) pay compensation for failure to deliver and for the poor customer service (say £100?), and (c) for a deadlock letter if they can't agree to your terms.
A deadlock letter is used to take a matter to CISAS if VM choose not to resolve it to your satisfaction. Without a deadlock letter you can still approach CISAS, but need to wait eight weeks from VM getting the formal complaint.
